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Our team of subject expert teachers has prepared and reviewed the NCERT Solutions for Class 6 Science Chapter 12 Electricity and Circuits are given here will help you to prepare well and score good numbers in exams.
Electricity and Circuits NCERT Solutions for Class 6 Science Chapter 12
Class 6 Science Chapter 12 Electricity and Circuits Exercise Questions and Answers
Question 1.
Fill in the blanks:
- A device that is used to break an electric circuit is called ………………………….
- An electric cell has ………………………… terminals.
Answer:
- switch
- two
Question 2.
Mark ‘ True ’ or ‘ False ’ for the following statements:
(a) Electric current can flow through metals.
Answer:
True
(b) Instead of metal wires, a jute string can be used to make a circuit.
Answer:
False
(c) Electric current can pass through a sheet of thermocol.
Answer:
False
Question 3.
Explain why the bulb does not light up in the arrangement shown in Fig. 12.5.
Answer:
We know that a bulb lights up only when the bulb and wire form a complete path, which starts at one terminal of the electric cell and ends at the other terminal. Here in this arrangement, the circuit is not completed. The handle of the screwdriver is made of some material which is an insulator. That is why the bulb will not glow.
Question 4.
Complete the drawing shown in Fig. 12.6 to indicate where the free ends of the two wires should be joined to make the bulb glow.
Answer:
Question 5.
What is the purpose of using an electric switch? Name some electrical gadgets that have switches built into them.
Answer:
A switch is a simple device that either breaks the circuit or completes it. Hence we use electric switches in order to either
- stop an electrical gadget in function when required or
- to start an electrical gadget when needed.
Some electrical gadgets that have switches built into them are electric iron, table fan, television set, radio, etc.
Question 6.
Would the bulb glow after completing the circuit shown in Fig. 12.8 if instead of a safety pin we use an eraser?
Answer:
No, the bulb will not light up. This is because an electric bulb lights up only when the circuit is completed and the eraser is a non-conducting material.
Question 7.
Would the bulb glow in the circuit shown in the figure:
Answer:
No, the bulb will not light up because the woolen thread is an insulator and hence current will not flow through it.
Question 8.
Using your “conduction tester” on an object makes the bulb light up. Is the material of that object a conductor or an insulator? Explain.
Answer:
The material of that object is a conductor. Because with this object bulb lights up showing that electricity is flowing in the circuit, i.e., the circuit is complete. This is possible only if the material of the object allows the electricity to pass through it and we know only conductors allow the electricity to pass, thus the material of the object must be a conductor.
Question 9.
Why should an electrician use rubber gloves while repairing an electric switch at your home? Explain.
Answer:
Yes, the electrician should use rubber gloves while carrying out electrical repairs because rubber is an insulator. So the electrician will not get electric shocks due to leakage of electricity.
Question 10.
The handles of the tools like screwdrivers and pliers used by electricians for repair work usually have plastic or rubber covers on them. Can you explain why?
Answer:
With screwdrivers, the electrician has to touch naked wires and screws in which electricity is flowing. If the screwdriver will have no handle made of plastic or wood, the electricity will flow through the screwdriver to his body, which is itself a good conductor of electricity and he has to face an electric shock. If handles are coated with wood or plastic, which are insulators, that will check this flow of electricity, thus making him safe from electric shock.
Question 11.
Will the torch bulb light up in the following arrangement?
Answer:
Yes.
Question 12.
The inside of a torch looks like this.
When we close the switch, the circuit is completed and the bulb lights up. Draw a red line on the figure indicating the complete circuit?
Answer:
Class 6 Science Chapter 12 Electricity and Circuits InText Questions and Answers
Activity 1
Take a torch that works on two electric cells. Open it and take out the electric cells. Insert them again in different arrangements and press the switch. Does the bulb light up each time?
Answer:
No, the bulb does not light up each time.
Activity 2
Collect several kinds of materials to test, such as coins, cork, rubber, glass, keys, pins, plastic scale, wooden block, pencil lead, aluminium foil, candle, sewing needle, thermocol, mica, pencil lead. Touch the free ends of the bare wires of the conduction tester to each sample (Fig. 12.4) Make sure that the two wires do not touch each other.
Does the bulb always light up? Make a table similar to the Table, in your notebook and record your observations.
Answer: