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6th Sample Papers

Energy is very important for our life. Most of our domestic activities are run by electric energy. Electric energy is a form of energy generated using hydro energy plants, nuclear plants, windmills, coal and solar resource. It is very essential to understand the phenomenon of electricity as it can be very dangerous if used improperly. Electric current needs a circuit to function. A circuit is the combination of battery, a wire, switch, a bulb or any other device. Let us refresh our knowledge on the lesson electricity and circuits with the help of question answers. You will also find some additional question answers which could help your exam preparation.

Important question answers

I. Fill in the blanks

  1. A device that is used to break an electric circuit is called Switch.
  2. An electric cell has two terminal’s.
  3. An electric circuit has a battery, a switch, a wire and a bulb.
  4. The two terminals of a circuit are positive and negative
  5. A fuse helps to protect a circuit when excess current flows into a circuit.
  6. The substances that allow electricity to flow through them are called conductors.
  7. Copper is a very good conductor among all metals.
  8. Pure water doesn’t conduct electricity.
  9. Human body receives shock because it is a good conductor of electricity.

II. Mark ‘ True” or ‘False’ for the following statements

  1. Most of the metals are good conductors of electricity.
  2. Electric current can flow through rubber material.
  3. Vegetables doesn’t allow the electricity through them.
  4. Iron thread is used in a fuse.
  5. Electric current can help us to makeelectromagnets.
  6. Instead of metals wires, a jute string can be used to make a circuit .
  7. Electric current can pass through a sheet of thermocol .
  8. Electricians must wear gloves while repairing electric devices.
  9. It is not a good idea to repair electrical devices while it is raining outside.

III. Answer the follwoing

1. Explain why the bulb would not glow in the arrangement show in fig
Answer: The bulb in the above circuit cannot glow as one end of tester/ screw driver is made up of plastic which is an insulator. Insulators doesn’t conduct electricity

2. Complete the drawing shown in Fig 12.9 to indicate where the free ends of the two wires should be joined to make the bulb glow
Answer:In the setup given below, the circuit is open. We need to make contact between the two ends of the steel pin to make a continuous circuit which will allow the flow of current

3. What is the purpose of using an electric switch. Name some electrical gadgets that have switches built into them.
Answer: An electric switch helps in making as well as breaking the circuit without removing the connection When switch is ON, the current will flow in the circuit, thus, it also saves electricity and make the use of appliances easier. Some electric gadgets are: Television, iron box, Washing machine, Refrigerator etc

4. Would the bulb glow after completing the circuit shown in Fig below if instead of safety pin we use an eraser
Answer: No, the bulb will not glow when we use an eraser instead of safety pin even after circuit is complete because rubber is an insulator and current will not flow through it


5. Would the bulb glow in the circuit shown in the setup below.
Answer: No, the bulb will not glow because the wires from both terminal of the battery are connected to the one terminal of the bulb. In order to make the bulb glow, wires should be connected to the terminals of the bulb

6. What are home appliances?

Answer: The most common electrical items used at our home are called appliances. Some of them are; iron box, refrigerators, electrical stove etc.

7. How does a battery work?

Answer : A battery is a device filled with chemical substances which gets converted into current when connected in a circuit

8. How must we connect a group of batteries together to make them work?

Answer : When we want to add many batteries in a single circuit, it is important to connect positive terminal to the negative terminal. A group of batteries must be arranged in alternating positive and negative terminals (+, -, +, -).

9. Why do we prefer copper in most of the electric wires?

Answer: Because, copper is a very good conductor when compared to any other metals

10. What are some precautions we must take when handling electrical devices?

Answer: We must switch off the mains before repairing any electrical equipment. Wear gloves and rubber footwear to avoid earthing effect. Never touch any electrical devices with wet hands. Check the wiring and coils of equipment regularly.

11. Using the ‘conduction tester’ on an object it was found that the bulb begins to glow. Is that object a conductor or an insulator? Explain.
Answer: That object must be a conductor because it allows the current to flow through it and thus helped in the glowing of bulb.\

12. Why should an electrician use rubber glows while repairing an electric switch at your home ? Explain.
Answer: Rubber gloves are insulators, so they do not allow the current to flow through them. Therefore an electrician uses rubber gloves while repairing an electric switch

13. The handles of the tools like screwdriver and pliers used by electricians for repair work usually have plastic or rubber covers on them can you explain why?

Answer: The handles of the tools like screw-driver and pliers used by electrician for repair work usually have plastic or rubber covers on them as plastic is an insulator which protect electricians from severe electric shocks and accidents

14. How does a fuse works in a circuit?

Answer: A fuse is usually made of aluminum wire, which is sensitive to excess heat and current. When a heavy current flows from mains, the fuse melts leading to the breakage of circuit. Current cannot flow through the broken circuit until à new fuse wire is being installed into the fuse box.