Electric Bulb

Q.

Filament of a bulb is made up of:

1. Aluminum

2. Tungsten

3. Copper

4. Iron

Q.

What is the function of the filament in an electric bulb? [1 MARK]

Q. Draw the electric symbol of the cell and the battery. Also, briefly mention which part of the battery symbol shows positive and negative terminals.

Q.

Why are compact fluorescent lamps (CFLs) preferred over electric bulbs?

Q. ____ is a device which converts electrical energy into heat energy and light energy.

1. Motor
2. Bulb
3. Battery
4. Transformer

Q.

The thin wire that gives off light in a bulb is known as:

1. None of these

2. Filament of the bulb

3. Wire of the bulb

4. Shape of the bulb

Q.

Heating effect of electric current is used in___.

1. Filament bulb

2. An iron

3. Microwave oven

4. All of the above

Q.

What is the full form of LED ? Why are LED bulbs considered energy efficient? Now explain why LED bulbs are preferred over filament bulbs.
[5 MARKS]

Q. Why are asbestos sheets used for laying the roofs of some houses?

1. They are good conductors of heat
2. They are bad conductors of heat
3. They are costly
4. They have nice look

Q.

What is the difference between open and closed circuit?

Q. How does an electric bulb produce heat

Q.

What is the function of the filament in an electric bulb? What is the principle on which working of a bulb is based on? [2 MARKS]

Q. The same amount of current flows through the connecting wires and the bulb filament. However, it is only the filament that glows. Why?

Q.

What are the commonly used electrical components in an electric circuit?

Q. Why does heat is not produces in CFL bulbs?(3marks)

Q. Draw the electric symbol of the cell and the battery. Also, briefly mention which part of the battery symbol shows positive and negative terminals.

Q. Identify the part of the bulb which generates most heat in the bulb:

1. 
2. 
3. 
4. 

Q. Which among the following statements about an electric bulb are correct?

1. It consists of an iron chamber fixed on a glass base.
2. It has a filament.
3. It has a plastic filament.
4. It has a glass chamber fixed on a metal base.

Q. Pins Q, P, R, and S are attached to the iron rod with the help of wax as shown below. In which ascending order the pins are likely to fall?

1. P, Q, R, S
2. Q, P, R, S
3. S, R, Q, P
4. S, R, P, Q

Q.

What are the necessary items required to build an electric torch?

1. Power station

2. Railway station

3. Airport

4. None of these

Q. Match the following pictures of devices to their names.

1. 
2. Siphon
3. 
4. Pressure Guage
5. 
6. Barometer

Q. An electric bulb consists of ___________ terminal/s.

1. one
2. two
3. three
4. six

Q. What are the factors upon which the amount of heat produced in a wire depend?

(i) Material of the wire​
(ii) Length of the wire​
(iii) Thickness of the wire

1. 
   Only (i)
2. 
   (i) and (ii) only
3. 
   (i), (ii), and (iii)
4. 
   (ii) and (iii) only

Q. What are the factors upon which the amount of heat produced in a wire depend?

(i) Material of the wire​
(ii) Length of the wire​
(iii) Thickness of the wire

1. 
   Only (i)
2. 
   (i) and (ii) only
3. 
   (i), (ii), and (iii)
4. 
   (ii) and (iii) only

Q. For the circuit given below, which of the given statements are correct?

1. The circuit is closed.
2. The circuit is open.
3. No current flows through the bulb.
4. Current flows through the bulb after some time.
   

1. Only 2 and 3
2. Only 1 and 3
3. Only 2 and 4
4. Only 1 and 4

Q.

Electrical gadgets are now available with stars on them. Buildings are marked as green buildings, green schools, etc. What does it mean? Should we go for such gadgets and practice? Which values are shown?

Q.

What are the necessary items required to build an electric torch?

1. Power station

2. Railway station

3. Airport

4. None of these

Q.

State the energy while using the electric bulb.

Q. For the effective radiation of heat by an electric room heater, which of the following can be done to the reflector panel?

1. Paint it red
2. Polish it
3. Paint it green
4. Paint it black