Ranger is used for addition, subtraction, multiplication, and division to ten. 

Tux Math is an open source arcade - style video game for learning arithmetic. The main goal is to make learning effective and fun.

 Save option shortcut key is Ctrl+S.

a) Human being - Homo sapiens
b) Paddy - Oryza sativa

Binomial nomenclature is an universal system of naming organisms. As per this system, each organism has two names like Genus name and Species name.

Bacteria and Blue green algae are examples for monera.

It is a tool used to classify organisms based on their similarities and differences.

Lysosomes are the main digestive compartments of the cell. They lyse a cell. So it is called as scavengers of the cell.

Cell membrane is the boundary of animal cell.

Chromatin and nucleolus are the main things of nucleus.

Chloroplast is a organelle uses energy from sunlight to make starch.

Melting is associated when ice melts.

It grows regular interval time. so it is called periodic change.

It is a exothermic change.

Rotation and Revolution of the earth, Beating of the heart.

Batteries are a collection of one or more cells.

Electric bulb, geyser, iron box, immersible water heater are the devices that run using heat effect of electric current.

Fuse is a safety device which is used in household wiring and in many appliances.

SI unit of electrical conductivity is Siemens / meter (S/m)

The kink prevents the mercury from flowing back into the bulb when the thermometer is taken out of the patients mouth.

Gas molecules are randomly moved. So it is not possible to measure temperature of air by clinical thermometer.

It is wrong. Clinical thermometer indicates only 35°C to 42°C. So hot water is greater than 42°C. So it is wrong.

Kodaikanal temperature is greater. The different temperature is
-4°C + 3°C = 7°C

Pictures are of two types,
(i) Vector,
(ii) Raster.

Photoshop is a software used to beautify and edit the photos. It is used by Photographers.

Polio, Tuberculosis.

(i) The surroundings should be kept clean.
(ii) Drains should be covered properly.

(i) Mangrove plants roots which are seen above the ground for the purpose of gaseous exchange.
(ii) These roots are erect, peg like structures with numerous pores through which air circulates.
(iii) These roots are called breathing roots, or pneumatophores. e.g Avicennia.

Runner, stolum, sucker, offset.

(i) A stamen consists of two parts.
(ii) A stalk called filament and a lobe called anther. The anther contains pollen grains.

A - mass number, Z - atomic number.

Atoms of different elements with different atomic number and different mass numbers but the same number of neutrons are called isotones.

1.6726 x 10^-27 kg.

Neutron is an elementary particle that carries no charge

H₂SO₄
H₂ = 2 Hydrogen atoms
S = 1 Sulphur atom
O₄ = 4 Oxygen atoms
Hence its atomicity is 2 + 1 + 4 = 7

Molecule is the smallest unit of compound.

118.

1. Increase the area of its base.
2. Lower its centre of gravity

Mass, distance, speed, temperature.

No, displacement is a vector quantity as it depends on direction.

4.22 light years.

Water

Wooden block.

By using measuring cylinder.

Graphical method.

Coulomb (C)

mole (mol)

m/s

a. Volume of a cube = side \(\times\) side \(\times\) side
= 3 cm \(\times\) 3 cm \(\times\) 3 cm = 27 cubic cm or \(\mathrm{cm}^{3}\)
b. Volume of a cylinder \(=\pi \times(\text { radius })^{2} \times \text { height }\)
\(=22 / 7 \times 3 \times 3 \times 7=198 \mathrm{~m}^{3} .\)

(a) Area of rectangle = length \(\times\) breadth
= 12 \(\times\) 4 = 48 m²
(b) Area of circle
\(=\pi \times r^{2}=(22 / 7) \times 7 \times 7 \\ =154 \mathrm{~m}^{2}\)
(c) Area of triangle
\(=1 / 2 \times \text { base } \times \text { height } \\ =1 / 2 \times 6 \times 8=24 \mathrm{~m}^{2}\)

Area of a square = side \(\times \) side
= 1 m \(\times \) 1 m
= 1 m² or 1 square metre
Area of 10 squares = 1 square metre \(\times \) 10
= 10 square metre

(i) One of the nucleon located in the nucleus.
(ii) Positively charged particle (+1).
(iii) Mass of a proton is 1.6726 \(\times\) 10^-27 kg.

Protons, neutrons and electrons.

An atom is the smallest particle of a chemical element that retains its chemical properties.

I agree this statement. Because if we washed with cold water leads to prevent from more tissue damage.

Don't use mobile frequently. If you are using frequently it may leads to loss your vision. Because of heavy light focus can damage our lens leads to irritation.

The regular hair wash and massage of the scalp will remove the dead skin cells, excess oil and dust.

We have to eat foods rich in antioxidant vitamins and minerals, use of antibiotic eye drops or ointment to protect the eyes.

There are two possible answers:
Velocity gives an idea of how fast the position changes. or Acceleration gives an idea of how fast the velocity changes.

She moves in a straight line with constant velocity.

An object moving in uniform circular motion is moving around the perimeter of the circle with a constant speed. While the speed of object is constant, its velocity is changing, Ex: Merry-go-round, roller coaster, planets orbiting the sun.

Elemenls: Iodine and Lithium.
Compounds: Water, Common salt, Sugar and Carbon dioxide.

i) Chemical formula is a symbolic representation of one molecule of an element or a compound
ii) It provides information about the elements present in a molecule and the number of atoms of each element.
Significance:
The types of atoms and the number of each types of atoms in one molecule of substance can be known by chemical formula.

Molecules of elements: O₂ and N₂
Molecules of Compounds: CO₂ and NaCl.

(i) The two dimensional (2D) images have only the two dimensions - length and height.
(ii) But three dimensional images (3D) have length, height and width. 3D images appear in front of our eyes like it happens in the real world.

Raster graphics are created on the basis of pixels. When we enlarge this types of photos, we could see the pictures as rectangular layers or grids.

Leaves on the stem are modified into spine in green succulent plant is called as thorns.

In climbers, the leaf of plant would be modified into elongated structure to help the plants climb efficiently is known as tendril.

Insects, birds, animals, wind and water are the agents of pollination.

The process by which pollen grains reach stigma is called as pollination.

Two types of reproduction are,
i) Sexual reproduction.
ii) Asexual reproduction.

Density of gold is 19,300 kg/m³

Astronomical unit and light year.

Iron ball sinks in all the liquids apart from mercury.

Density (D) = mass (M) / volume (V).

Volume of a cylinder = π r² h

One light year = 9.46 \(\times\) 10¹⁵m

Area, Volume, Speed, Electric charge and Density.

Merits of five kingdom:
i) This system of classification is more scientific and natural.
ii) This system of classification clearly indicates the cellular organisation, mode of nutrition and characters for early evolution of life.

The levels of classification are 
1. kingdom
2. phylum
3. classes
4. order
5. families
6. genus and
7. species

Cell, tissue, organ, organ system, organism

Smooth ER and Rough ER

Cell wall and Cell membrane

Chloroplast and Mitochondria

\(\begin{array}{|l|l|} \hline {\text { Dissolution of sugar }} & \text { Burning of sugar } \\ \hline \text { It forms a solution } & \text { It forms ash. } \\ \hline \text { It is a physical change } & \text { Chemical properties changed } \\ \hline \text { It will be reversible } & \text { It is irreversible } \\ \hline \text { No heat changed } & \text { Heat released } \\ \hline \end{array}\)

i) Temperature variation can change the substance.
ii) Every substance has a melting point. It attain the melting temperature substance can change.

\(\begin{array}{|c|l|l|} \hline \text { S.No. } &{\text { Physical change }} &{\text { Chemical change }} \\ \hline \text { 1. } & \text { No new substance are formed } & \text { New substance are formed } \\ \hline 2 . & \text { Chemical properties do not change } & \text { Chemical properties changed } \\ \hline 3 . & \text { It is a temporary action. } & \text { It is a permanent action. } \\ \hline 4 . & \text { It is a reversible reaction } & \text { It is a irreversible reaction. } \\ \hline \end{array}\)

The flow of electric charges constitute an electric current. An electric current is measured by the amount of electric charge moving per unit time at any point in the circuit

Yes, Ramani's statement is correct. I agree Ramani statement. because laboratory thermometer has no kink. When thermometer is taken out from the hot water, the mercury level will fall. We can't measure the correct temperature.

a) Its expansion is uniform (for equal amounts of heat it expands by equal length)
b) It is opaque and shining
c) It is a good conductor of heat.
d) It does not stick to the sides of the glass tube.
e) So mercury is used in the thermometer
f) Water cannot used in thermometer.
1) Its expansion is not in uniform.
2) It is stick to the sides of the glass tube.

No, since the dog was vaccinated regularly, there is no chance of the person suffering from Rabies. But still the person should seek medical advise for the treatment

(i) We must brush our teeth at least twice a day.
(ii) We must have a shower daily.
(iii) We must wash our hair regularly.
(iv) We must wash our face and hands regularly.
(v) We should keep food covered with a lid.
(vi) We should wear washed and clean clothes.
(vii) We must wear slippers while we go out of the house.
(viii) Drinking water must be stored in a clean and safe place.

When we are suffering from cold etc, the virus comes out with the droplets and spreads in air. This can infect a healthy individual. Thus we should use a handkerchief while sneezing.

(i) Causal-agent: Chickenpox (chicken pox), also known as varicella, is a highly contagious infection caused by the varicella zoster virus.
(ii) This disease spreads through air and contact with an infected person.
(iii) Symptoms: A appearance of rashes on the whole body, fever, headache and tiredness.
(iv) Prevention and treatment: The chickenpox (Varicella) vaccine is the best way to prevent chickenpox. Special attention should be given to the infected persons.

(i) Communicable diseases do not spread from person to person. They are caused by other factors.
(ii) Antibiotics, or medicines that fight against germs, do not help to cure noncommunicable diseases.
(iii) Problems caused by wearing out of body parts: Rheumatism, heart attack, epileptic seizures, stroke, migraine headaches, Cataract and cancer.
(iv) Problems caused by external harmful agents entering the body: Allergies, asthma, poisons, snakebite, cough from smoking, stomach ulcer, alcoholism.
(v) Problems caused by a lack of trace elements in the body: Anaemia, pellagra, night blindness and xerophthalmia, goiter and hypothyroidism.

Mangrove plants are found in swampy regions where there is water logging and oxygen available for roots will be less. The breathing roots grow above the soil and have pores for gaseous exchange. This helps the roots to get more oxygen with the help of breathing roots

Parasites are plants which live on other living plants and derive nutrients from them. They are non-green and do not photosynthesize. They have sucking roots to absorb the nutrients directly from the host tissue. Thus they lack leaves.

Chrysanthemum
Modification: Sucker (sub aerial stem modification).

(i) These plants grow in nitrogen deficient places. In Nepenthes, the leaves are modified into a flask like structure, which is used to attract insects and other tiny animals.
(ii) The inner wall of the leaf secretes digestive enzymes that help to digest the insects and extract the nitrogen needed for the plant. E.g: Nepenthes.

(i) Plants growing in deserts try to store water. If the surface area is large, more water is lost by evaporation.
(ii) In plants like cactus, the stem is thick and becomes flat like leaves to do photosynthesis.
(iii) The leaves are reduced to small spines with less surface area. This kind of modification is called phylloclade. e.g. cactus.

Many Plants require additional support. Such plants develop roots on their aerial parts to provide mechanical support. These roots grow downward and act as supportive organs. There are three types of modified roots for support.
(i) Prop roots : Roots are modified to provide mechanical support as seen in Banyan tree. These roots grow vertically from horizontal branches of a tree.
(ii) Stilt roots : In sugarcane, and maize adventitious roots arise from the nodes in cluster at the base of the stem. These roots are called stilt roots which gives additional support.
(iii) Climbing roots : In betel and black pepper, nodes or interrnodes bear roots which help in climbing.

Electrons carry a negative electric charge, and protons carry a positive charge. The attraction between them holds electrons in orbits.

(i) 31
(ii) 15.

J.J. Thomson's theory does not propose anything about the positive and negative charges of an atom. Hence, it was not able to explain many of the properties of substances.

Atoms that have the same mass number but different atomic numbers are called Isobars. Eg: Calcium - 40 and Argon - 40

Atoms of the same element can have different number of neutrons. Such atoms will have same atomic number but different mass numbers. These atoms are called isotopes. For example Hydrogen has three isotopes Hydrogen (₁H¹), Deuterium (₁H²), Tritium (₁H³).

Atomic mass number (A) is equal to the sum of the number of protons(p) and neutrons (n) in the nucleus
Atomic mass or mass number = Number of Protons + Number of Neutrons

Yes It is similar to the solar system. It has a core center called nucleus and it has paths called orbits around the nucleus.

Hydrogen is considered as an element because,
(i) Hydrogen cannot be broken into new substance by ordinary physical or chemical means. (i.e) by applying heat, light.
(ii) Hydrogen has one kind of atoms.

When air inside the hot air balloon is heated with a burner, it expands. The expansion causes the density of the air inside the balloon to decrease. Hence, the air inside the balloon has a lower density that the air outside of the balloon. This difference is density allows the hot-air balloon to float.

(i) SOLID: When solid is heated, the particles gain energy and vibrate more vigorously.
(ii) LIQUID: Melting occurs when the melting point is reached. The solid changes to its liquid state.
(iii) LIQUID: When a liquid is heated the particles gain energy and vibrate more vigorously.
(iv) GAS: Boiling occurs when the boiling point is reached. The liquid changes to its gaseous State.

(i) The properties of a compound are different from those of its constituent elements.
(ii) A compound cannot be broken down by physical methods. This is because a compound is made up of different elements that are chemically combined. Sodium chloride cannot be separated by physical methods such as filtration

a) Mercury,
b) Silver, Copper

Metalloids are the elements which have properties intermediate, between those of metals and non-metals. Ex. : Boron, Silicon, Germanium, Arsenic, Antimony.

There are 118 known elements till date. 94 of these elements occur naturally while 24 elements have been created artificially in the laboratory

On earth the three most abundant atom are iron, oxygen, and silicon.

The smallest unit of an element that exhibits the properties of the element is called as 'atom'.

Stability is a measure of the body's ability to maintain its original position.
The three types of stability are
(a) Stable equilibrium
(b) Unstable equilibrium
(c) Neutral equilibrium

If either speed or direction changes, then the velocity is non uniform. Eg. a train starting and moving out of the station.

Speed is the rate of change of distance
Formula: Speed = distance /time
Unit is meter/second (m/s)

Initial velocity (u) = 0 km/h
Final velocity (v) = 40 km/h
Time (t) = 10 min = \(\frac{10}{60h}=\frac{1}{6h}\)
Acceleration (a) = \(\frac{v-u}{t}=\frac{40-0}{\frac{1}{6}}\) = 40 x 6 = 240 km/h

Total displacement = 320m
From A to C displacement = 320 - 100 = 220 m

Time taken = 3 min 40 see
= 180 + 40 = 220 s

Average velocity = 1 m/s

(i) Nautical mile is the unit for measuring the distance in the field of aviation and sea transportation. One nautical mile is 1.852 km.
(ii) The unit for measuring the speed of aeroplanes and ships is knot. One knot is the speed taken to travel one nautical mile in hour.

The centre of gravity and the total weight of the doll is concentrated at its bottom most point, generating a dance-like continuous movement with slow oscillations.

(i) Luggage compartment of a tour bus is located at the bottom and not on the roof.
(ii) Racing cars are built low and broad for stability.
(iii) Table lamps and fans are designed with large heavy bases to make them stable.

Distance covered after 2 complete rounds
= 2 x circumference of a circle
Distance = 2 x 2 π(2R) = 8π(2R)
After 2 complete rounds, the body comes back to its initial position.
so, displacement = 0

The matter (atoms and molecules) is more densely packed in iron. Whereas is wooden block the matter is loosely packed.
In the language of science, we will say that the density of iron is more than the density of wooden block

One light year is defined as the distance traveled by light in vacuum during the period of one year. 1 light year = 9.46 x 10¹⁵ m.

One astronomical unit is defined as the average distance between the earth and the sun. 1AU = 1.496 x 10¹¹m or 149.6 x 10⁶ m

Density = \(\frac{mass}{volume}\)

The volume of liquid which a container can hold is called its capacity

Area is the measure of the region inside a closed line.

Comparison of an unknown quantity with a standard quantity is called measurement

The known measure of a physical quantity is called the unit of measurement

A quantity that can be measured is called a physical quantity.
For example, the length of a piece of cloth, the time at which school begins.

Mass is the amount of matter contained in a body. It's unit is kilogram (kg).

Density of cylinder \(=\frac { mass \ of \ cylinder }{ volume \ of \ cylinder }\)
\(=\frac{280}{4}=70 \mathrm{~kg} / \mathrm{m}^{3}\)

(i) To save the life
(ii) To prevent further bleeding and determine the condition of the patient.
(iii) To relive the pain
(iv) To provide a medical care available at the earliest.

The centre of gravity of an object is the point through which the entire weight of the object appears to act.

An object undergoes uniform acceleration when the change (increase or decrease) in its velocity for every unit of time is the same.

(a) A bus moving with constant speed.

\(\begin{array}{|l|c|c|c|c|c|} \hline \text { Time } & 0 & 1 & 2 & 3 & 4 \\ \hline \text { Distance } & 0 & 10 & 20 & 30 & 40 \\ \hline \end{array}\)
(b) A car parked on road side.

 

\(\begin{array}{|l|c|c|c|c|c|} \hline \text { Time } & 1 & 2 & 3 & 4 & 5 \\ \hline \text { Distance } & 20 & 20 & 20 & 20 & 20 \\ \hline \end{array}\)

(i) H₂SO₄ consists of 2H atoms, 1 S atom and 4 O atoms.
(ii) Hence, Atomicity = 2 + 1 + 4 = 7

The total number of atoms present in one molecule of an element, Compound or a substance is called atomicity

A compound is a chemical substance formed by the combination of two or more elements in definite proportions.
Example:
H₂O:
\(2 \mathrm{H}_{2}+\mathrm{O}_{2} \rightarrow 2 \mathrm{H}_{2} \mathrm{O}\)
(2    :   1)
NaCI:
\(2 \mathrm{Na}+\mathrm{Cl}_{2} \rightarrow 2 \mathrm{NaCl}\)
(2    :   1)

In Acacia auriculiformis, petioles expand to form leaf like structure. They carry out the function of leaf (Photosynthesis). This modification is known as phyllode.

One astronomical unit is defined as the average distance between the earth and the sun.
1 AU = 1.4965 10⁶ km = 1.496 \(\times\) 10¹¹m.

One light year is defined as the distance travelled by light in vacuum during the period of one year.
1 Light year = 9.46 \(\times\) 10¹⁵m

Density of a substance is defined as the mass of the substance contained in unit volume (1 m³).
Density (D) = mass (M)/volume(V)
D = M/V
SI unit of density - kg/m³

Physical quantities which can be obtained by multiplying, dividing or by mathematically combining the fundamental quantities are known as derived quantities.
Ex: Area, volume

This is Animal cell. The boundary of the cell is known as cell membrane. Inside the cell membrane many tiny organelles present in the cytoplasm. The cell organelles are golgi apparatus, Lysosomes, Ribosomes, Rough and Smooth endoplasmic reticulum, mitochondria and nucleus, Mitochondria is the power house of the cell. The energy produced with in the mitochondrian is used for all the metabalic activities of the cell. Lysosomes are called as suicidal bags because they are the main digestive compartments. Endoplasmic reticulum synthesis of protein lipid and steriods. Nucleus is the brain of the cell. It controls all the processes of chemical reactions that take place inside the cell.

(i) Golgi Complex:
Membrane bounded sacs are stacked on top of the other with associated secretory vesicles are collectively known as golgi complex. Functions of golgi complex are the production of secretory substances, packaging and secretion. This is the secret behind the change in the colour and taste of fruits.
(ii) Lysosome:
You will find organelles called as lysosomes, which are very small to view using a light microscope. They are the main digestive compartments of the cell. They lyse a cell, hence they are called "suicidal bag".
(iii) Nucleus:
Plant and animal cells have a nucleus inside the cytoplasm. It is surrounded by a nuclear envelope. One or two nucleolus and the chromatin body are present inside the nucleus. During cell division, the chromatin body is organised into a chromosome. Storage of genetic material and transfers heredity characters from generation to generation are the functions of chromosome.

(i) Dry cells are normaly used in small devices such as remote control for T.V., torch, camera and toys.
A dry cells is a portable form of a leclanche cell. It consists of zinc vessel which acts as a negative electrode or anode the vessal contains a moist paste of saw dusts saturated with a solution of ammonium chloride and zinc chloride. The ammonium chloride acts as an electrolyte.
(ii) Electrolytes are substances that become ions in solution and acquire the capacity to conduct electricity.
(iii) The purpose of zinc chloride is to maintain the moistness of the paste being highly hygroscopic. The carbon rod covered with a brass cap is placed in the middle of vessel. It acts as positive electrode or cathode.
(iv) It is surrounded by a closely packed mixture of charcoal and manganese dioxide (MnO₂) in a muslin bag. Here MnO₂ acts as depolarizer. The zinc vessel is sealed at the top with pitch or shellac. A small hole is provided in it to allow the gases formed by the chemical action to escape. The chemical action inside the cell is the same as in leclanche cell

Anaemia Causes:
It is caused by eating food with less iron content and can also be caused due to feeding some other foods instead of breast milk for babies.
The signs of anemia are:
(i) Pale or transparent skin, the inner surface of eye lids are pale, white fingernails, pale gums, weakness and fatigue.
(ii) In severe cases, face and feet may be swollen, the heartbeat is rapid and with shortness of breath.
(iii) Children and women who eat mud are usually anaemic. Consuming iron containing food
(i) Food - Moringa leaves, Dates, Liver (Sheep and Chicken), Green leafy vegetables like beans, peas, lentils and Greed banana.
(ii) Pills- Cod liver oil tablet, Ferrous sulfate.

Sub- aerial Modifications : Stem of some plants remains sub- aerial which grow horizontally on the surface of the soil for the purpose of reproduction. There are four types.
(i) Runner: The stem grows laterally on the surface of the soil, breaks up to produce roots where it touches the ground to give rise to new plants. Eg: Centella (Vallarai).
(ii) Stolon: Stolon is a slender branch of the stem that grows upwards to some distance and then bends towards the ground. Upon touching the ground, it gives rise to a new plant. Eg.Wild strawberry.
(iii) Sucker: Sucker is a short and weak lateral branch that grows diagonally upwards and directly gives rise to a new shoot. Eg. Chrysanthemum.
(iv) Offset: An offset is a short and thick branch that arises from the axial part of a leaf. It has thick internodes. It produces a tuft of leaves and cluster of small roots below. Eg: Eichhornia.

John Dalton proposed the atomic theory in the year 1808.
(i) He proposed that matter consists of very small particles which he named as atoms.
(ii) An atom is smallest indivisible particle, it is spherical in shape.
(iii) His theory does not propose anything about the positive and negative charges of an atom.

(i) Proton (p): The proton is the positively charged particle and is located in the nucleus. Its positive charge is of the same magnitude as that of the electron's negative charge.
(ii) Neutron (n): Neutron is inside the nucleus. The neutron does not have any charge. Except hydrogen (protium), the nuclei of all atoms contain neutrons
(iii) Electron (e): This is a negatively charged particle. Electrons revolve around the nucleus of the atom in specific orbits. The mass of an electron is negligible as compared to that of a proton or neutron.

(i) Based on his experiment. Rutherford proposed his famous theory.
(ii) The fact that most alpha particles pass through the gold sheet means that the atom consists mainly of empty space.
(iii) The part from which the positively charged particles are turned back is positively charged but very small in size as compared to the empty space

(i) J.J. Thomson's theory proposed that the atom has positively charged part like the red part of the watermelon and in it are embedded, like the seeds, negatively charged particles which he called electrons.
(ii) According to this theory as the positive and negative charges are equal, the atom as a whole does not have any resultant charge
(iii) Thomson's greatest contribution was to prove by experimentation the existence of the negatively charged particles or electrons in an atom

(i) Symbol for some elements as proposed by Dalton.

(ii) The following rules are followed while assigning symbol to an elements:
(a) Chemical symbols usually consist of one or two letters
(b) The symbols of most elements correspond to the first letter (which is capitalized) of their English name. For example, the symbol for oxygen is "O" and that for hydrogen is "H".

(i) Place the irregular object on a graph sheet and draw its outline. Then remove the object
(ii) To find the area enclosed by the outline count the number of small squares.
(iii) If more than half-a-square is inside the boundary, count it as one otherwise neglect it.
(iv) The area of each small square is 1sq. mm.
(v) Area of the irregular object = No. of squares x 1 sq.mm.

(i) Take a measuring cylinder and pour some water into it.
(ii) Note down the volume of water from the readings of the measuring cylinder.
(iii) Take it as V₁
(iv) Now take Q small stone and tie it with a thread.

(v) Immerse the stone inside the water by holding the thread.
(vi) This has to be done such that the stone does not touch the walls of the measuring cylinder.
(vii) Now the level of water has raised.
(viii) Note down the volume. of water and take it to be V₂
The volume of the stone is equal to the raise in the volume of water.
V₁ = 30cc, V₂ = 40cc
Volume of stone = V₂ - V₁ = 40 - 30 = 10 cc

(i) Valency is defined as the combining capacity of an element.
(ii) The valency of the element with atomic number 8, Oxygen (2,6) is = 2.
(iii) The compound formed by oxygen with hydrogen is water. \(\mathrm{O}_{2}+2 \mathrm{H}_{2} \rightarrow 2 \mathrm{H}_{2} \mathrm{O}\)

i) Protons and neutrons in the nucleus of an atom are called as nucleons.
ii) They are located in the nucleus of an atom and are called so.
Properties:
i) Atomic mass is only depends on the mass of nucleous.
ii) They make the atom electrically neutral. (Protons - Positive, Neutrons - Neutral)
iii) Nucleons are similar in properties like mass except charge.

Atomic number (Z) = 26, Mass number (A) = 56
No. of protons P = 26
No. of electrons e = 26
No. of neutrons n = A - Z
= 56 - 26 = 30
Atomic structure of ₂₆Fe⁵⁶ is

Sub-atomic particles:
(i) Proton (p): This is the positively charged particle and it is located at the nucleus.
(ii) Neutron (n): Neutron is inside the nucleus. The neutron does not have any charge. Except hydrogen (protium), the nucleus of all atoms contain neutrons.
(iii) Electron(e): This is a negatively charged particle. Electrons revolve around the nucleus of the atom in specific orbits.

Disease are spread through air, water and some other organisms.
(i) Air = Spitting and coughing (Tuberculosis, chicken pox )
(ii) Contaminated waer = Drinking and cleaning by using unboiled water ( Cholera, Hepatitis).
(iii) Insects = Biting of infected insects like mosquito and flies. Dengue, Typhoid)
(iv) Animals = Through biting of in affected animals like dog, rabbit, cat etc,(Rabies).

First aid is the immediate treatment given to the victim of trauma or sudden illness before medical help is made available. For the following situation we have to give first aid,
i) Any vehicle accident other incident.
ii) Any burns due to heat, chemical or electricity
iii) If cut and scratches occur on the surface of the skin.
First Aid for skin Burning:
i) Affected area should be washed with cold water if severe burns occur, use of water should be avoided.
ii)  Antiseptic cream should be applied.
iii) The burnt area should be covered with a clean non-sticking cloth or bandages.

Tuberculosis:
(i) Causative agent  : Mycobacterium tuberculae bacteria.
(ii) Transmission : Spread from one person to another through air by spitting and prolonged contact with patient.
(iii) Symptoms : Fever, weight loss, chronic cough, bloody spitting and difficulty in breathing
(iv) Prevention and treatment : BCG vaccinations. Giving special attention to the patient. Regular medication like DOT
Chicken pox:
(i) Causative agent : varicella zoster virus.
(ii) Transmission : Spread through air and contact with infected person.
(iii) Symptoms : Appearance of rashes on the whole body, fever, headache and tiredness.
(iv) Prevention and treatment : Chicken pox vaccine is the best way to prevent. Special attention should be given to infected person
Robies:
(i) Causative agent: Virus (rhabdo virus)
(ii) Transmission : By the bite of the infected dog, cat, etc.
(iii) Symptoms: Hydrophobia, fever for 2-12 weeks and exaggerations
(iv) Prevention and treatment : Fatality can be prevented by timely vaccination before onset of symptoms.

Apparatus: Irregularly shaped plate, string, pendulum bob, stand.
i) Make three holes in the lamina.
ii) Suspend the lamina from the optical pin through one of the holes as shown.
iii) Suspend the plumbline from the pin and mark the position of the plumbline on the lamina.
iv) Draw lines on the lamina representing the positions of the plumbline.
v) Repeat the above steps for the holes.
vi) Label the intersection of the three lines as X is the position of the centre of gravity of the lamina.

Stability:
Stability is a measure of the body's ability to maintain its original position.
The three types of stability are
(i) Stable equilibrium
(ii) Unstable equilibrium
(iii) Neutral equilibrium
Stable Equilibrium:
i) The frustum can be tilted through quite a big angle without toppling.
ii) Its centre of gravity is raised when it is displaced.
iii) The vertical line through its centre of gravity still falls within its base.
iv) So it can return to its original position.


Unstable Equilibrium:
i) The frustum will topple with the slightest tilting. Its centre of gravity is lowered when it is displaced.
ii) The vertical line through its centre of gravity falls outside its base.

Neutral Equilibrium:
(i) It causes frustum to topple.
(ii) The frustum will rolls about but does not topple.
(iii) Its centre of gravity remains at the same height when it is displaced.
(iv) The body will stay in any position to which it has been displaced.

Properties of metalloids :
(i) Metalloids exhibit the properties of both metals and non-metals.
(ii) Unusually they look like metals but behave largely like non-metals,
(iii) They can form alloys like metals.

i) A compound is formed only when the constituent elements combine in a fixed proportion.
ii) Compound exhibits entirely different properties of their constituent elements.
iii) A compound cannot be broken down by physical methods.
iv) A compound can be separated into its constituent elements by chemical methods only.
v) Compound is made up of different elements that are chemically combined.

i) A compound is formed only when the constituent elements combine in a fixed proportion.
ii) Compound exhibits entirely different properties of their constituent elements.
iii) A compound cannot be broken down by physical methods.
iv) A compound can be separated into its constituent elements by chemical methods only.

i) Take a measuring cylinder and pour some water into it.
ii) Note down the volume of water from the readings of the measuring cylinder. Take it as V₁.
iii) Now take a small stone and tie it with a thread.
iv) Immerse the stone inside the water by holding the thread.
v) The stone should not touch the walls of the measuring cylinder.
vi) Note down the volume of water and take it to be V₂
vii) The volume of the stone is equal to the raise in the volume of water.
viii) Volume of stone = V₂ - V₁

Take a leaf from any one of trees in your neighbourhood. Place the leaf on a graph sheet and draw the outline of the leaf with a pencil. Remove the leaf. You can see the outline of the leaf on the graph sheet.
i) Now count the number of whole squares enclosed within the outline of the leaf. Take it to be M
ii) Then count the number of squares that are more than half. Take it as N
iii) Next, Count the number of squares which are half of a whole square. Note it to be P.
iv) Finally, count the number of squares that are less than half. Let it be a Q.
v) Now the approximate area of the leaf can be calculated using the following formula.
Approximate area of the leaf = M+(3/4)N+(1/2)P+(1/4)
This formula can be used to calculate the area of any irregularly shaped plane figures.

In underground modified stem, whole stem is burried under the ground and it has definite growth. Some stems that grow under the ground to store food. There are four types of underground stems they are,
i) Rhizome:
It is underground thick stem with nodes and internodes with scale leaves at the node.
(Eg) Ginger and turmeric.
ii) Corm:
This underground stem is round in shape and flat at the top and bottom. The daughter plants are arise from their buds. (Eg) Colocasia.
iii) Tuber:
It is an enlarged spherical underground stem and stores food. It has many dormant buds and it grows into a new plant. (Eg) Potato.
iv) Bulb:
It is a condensed stem which is disc like and stores food in the fleshy leaves.
The bulb has two types of leaves
1) Fleshy leaves - Inner part of stem
2) Scaly leaves - Upper part of stem
(E.g) Garlic and onion

The process by which pollen grains reach stigma of the flower is called as pollination. Pollination can be classified into two types based on their mode of transmission.
i) Artificial pollination:
The transfer of pollen grains from anther to stigma by manually is called as artificial pollination
ii) Natural Pollination:
1) The transfer of pollen grains from anther to stigma by insect or any other natural sources is called as natural pollination.
2) Pollination can be classified into another two types based on their site of transmission
i) Self pollination:
Pollen grains are transferred from the anther to the stigma of the same flower or to another flower of the same plant is known as self pollination.
ii) Cross pollination:
Pollen grains are transferred from the anther of one flower to the stigma of another flower of the same kind or different plant known as cross pollination.

Step 1: Open the application of 'Microsoft Photostory'. In that select "Begin A New Story" and click on Next.
Step 2: Click "Import Picture" in the next screen. Select 'Saved pictures' for video. If required, We can edit the image and click on Next.
Step 3: Now we can input small text, animation, audio effect for the picture then click Next.
Step 4: To provide background music, we can select a music file through "Select Music" and click on Next.
Step 5: select a title for the story, then through SETTINGS change the format of the video.
Step 6: Now our video is ready to view. Click "VIEW YOUR STORY". You can see your video now.

Kingdom fungi has saprophytic parasitic and symbiotic nutrition. It is a non green Eukaryotic. So it cannot prepare food. So it is saprophytic, parasitic and symbiotic nutrition

(i) Boiling of water is a physical change because it is a reversible action. No new substance is formed.
(ii) Boiling of egg is a chemical change because it is a irreversible action and new substance are formed.

Suddenly variation of temperature it shrinks so it will be cracks. so heat is obsorbed suddenly heat liberated it indicates a exothermic reaction.

(i) Yes, it is a chemical change.
(ii) Banana fruits contain an enzyme cailed polyphenol oxidase which cause chemical reaction when exposed to oxygen. Now the peeling banana colour is changed. So it is a chemical change.

1) The electric cell produce weak energy.
2) The bulb filament is broken. (dead)
3) The both wires are connected to the same terminal of the cell.
4) Battery or cell is dead.

\(\begin{array}{|l|c|} \hline \text { Animals and birds } & \text { Temperature (celsius) } \\ \hline \text { Dog } & 37.5-39.09 \\ \hline \text { Cat } & 38.0-39.5 \\ \hline \text { Rabbit } & 38.5-39.5 \\ \hline \text { Pigeon } & 41.0-44.1 \\ \hline \text { Crow } & 40.0 \\ \hline \text { Chicken } & 41.7 \\ \hline \end{array}\)

(i) Yes, an atom of an element has no electron will have the mass.
(ii) (Atomic mass, only depends on the mrmber of protons and the number of neutrons inside the nucleus. It is independent of number of electrons.)
(iii) Atom can exist with out electron and becomes a cation.
Ex: 
1) Hydrogen atoms (Z = 1) has only one electrons.
2) It loses one electron and becomes H⁺ ion
3) H → H⁺ + 1e^-
  (atom)    (Ion)

(i) Yes, I have came across such situation in some times. Because of the following reasons it may occur.
(ii) Due to heavy work body will become to tired.
(iii) If the mind is not take proper rest also leads to this situation.
(iv) To overcome these situation we have to keep our body and mind with proper rest.

When solid is heated, the particles gain energy and vibrate vigorously. The particles move slightly further apart from one another.
Hence, the volume increases due to the greater distance between the particles. But the size of the particles remains the same.

a) The matter begun to 'expand' when heated - 'Expansion'.
b) Ring and metal ball experiment is suitable for this hypothesis.
When the ball is heated, the ball has expanded and will not be able to pass through the ring until it has cooled.

Mostly leaves are arise from the stem in plants. In ginger the arial leaves are arise from underground and also the scaly leaves are also present in the rhizome. So ginger is consider as stem.