A ball of mass 1 kg moving with a speed of 10 ms^-1 rebounds after a perfect elastic collision with the floor. Calculate the change in linear momentum of the ball.

Find the final temperature of a copper rod. Whose area of cross section changes from 10 m² to 11 m² due to heating. The copper rod is initially kept at 90 K. (Coefficient of superficial expansion is 0.0021 /K)

What is the role of the earth wire in domestic circuits?

Why does an empty vessel produce more sound than a filled one?

A cobalt specimen emits induced radiation of 75.6 millicurie per second. Convert this disintegration in to becquerel (one curie = 3.7 × 10¹⁰ Bq).

Calculate the number of water molecule present in one drop of water which weighs 0.18 g.

a) State the reason for addition of caustic alkali to bauxite ore during purification of bauxite.
b) Along with cryolite and alumina, another substance is added to the electrolyte mixture. Name the substance and give one reason for the addition

Write notes on any two factors affecting solubility.

Explain the types of double displacement reactions with examples.

Arrive at, systematically, the IUPAC name of the compound: CH₃–CH₂–CH₂–OH.

Write a short note on mesophyll.

List out the parasitic adaptations in leech.

Trace the pathway followed by water molecules from the time it enters a plant root to the time it escapes into the atmosphere from the leaf.

What is bolting? How can it be induced artificially?

Why is vegetative propagation practiced for growing some type of plants?