Choose the incorrect statement.

1

(a)

A switch is the source of electric current in a circuit

(b)

A switch helps to complete or break the circuit

(c)

A switch helps us to use electricity as per our requirement

(d)

When the switch is open, there is an air gap between its terminals

In the circuit shown in figure, when the switch is moved to ON position.

1

(a)

the bulb A will glow first

(b)

the bulb B will glow first

(c)

the bulb C will glow first

(d)

all bulbs will glow together

Our body is

1

(a)

a bad conductor of electricity

(b)

sometimes a good conductor and sometimes a bad conductor

(c)

a good conductor of electricity

(d)

None of the above

Open circuit is called

1

(a)

switched ON

(b)

switched OFF

(c)

Both (a) and (b)

(d)

None of the above

Rubber is a

1

(a)

conductor

(b)

insulator

(c)

semiconductor

(d)

None of these

_________is an electric device which can easily close or open an electric circuit.

1

(a)

Filament

(b)

Electric bulb

(c)

Electric switch

(d)

Electric cell

Wood is a/an ______________

1

(a)

insulator

In bulb,_______________ glows.

1

(a)

filament

The handle of an electrician's screwdriver is made up of________________

1

(a)

insulator

Paper is not a__________________ material.

1

(a)

magnetic

The device used to break an electric circuit is called________.

1

(a)

switch

Electric current can flow through metals.

1

(a) False

(b) True

Electric current can pass through a sheet of thermocol.

1

(a) True

(b) False

The combination of two or more cells is called circuit.

1

(a) True

(b) False

Plastic is a good conductor of electricity.

1

(a) True

(b) False

Dry cell converts electrical energy into chemical energy.

1

(a) True

(b) False

What is electricity?

1

(a)

It is a form of energy.

Name two electrical devices.

1

(a)

Fan, bulb.

What is an electric cell?

1

(a)

It is a source of electricity.

How does an electric cell produce electricity?

1

(a)

The electric cell produces .electricitydue to chemical reactions that occur inside it.

Fig. shows a bulb with its different parts marked as 1, 2, 3, 4 and 5. Which of them label the terminals of the bulb?

1

(a)

Label 3 and 4 show the terminals of the bulb.

A fused bulb does not glow. Why? 

2

(a)

We should use plastic gloves for operating electrical devices. Explain why

2

(a)

Mention what type of materials can be used in electric circuit so that the current can pass through them.

2

(a)

Name some of the devices in which electric cells are used.

2

(a)

Name two insulators and two conductors.

2

(a)

1. Will the bulb glow in the circuit shown in figure? Explain.
   

   4

   (a)

2. Briefly explain about the components present inside the cell.

   4

   (a)

1. With the help of a labelled diagram, explain the structure and function of a torch?

   5

   (a)

2. Describe an electric cell with the help of a labelled diagram.

   5

   (a)

In figures A and B, show a bulb connected to a cell in two different ways.
(a) Mention the direction of the current through the bulb in both the cases (Q to P or P to Q)?
(b) Will the bulb glow in both the cases?
(c) Does the brightness of the glowing bulb depend on the direction of current through it?

5

(a)