Overloading and Short circuiting

Q.

Electric/electrical Switches are always connected to:

1. The Live wire

2. Either the Live wire or the Neutral Wire

3. The Neutral Wire

4. The Earthing Wire

Q.

When live wire comes in direct contact with the neutral wire the very high current flows through the circuit producing large amount of heat. This phenomenon is called

1. Short Circuit

2. Tripping

3. Fusing of wires

4. Earthing

Q.

Is it dangerous to touch a neutral wire

Q.

A fuse wire is inserted in a?

1. live wire

2. in the neutral wire

3. in the earth wire

4. may be connected in any line

Q. Explain the application of heating effect of electric current in a fuse.

Q. What is usual current rating of fuse wire in line to feed
1.Light and fans?
2.Appliances of 2KW or more power.

Q.

A square loop of wire lies in the plane of the paper. An increasing magnetic field is directed into the page. The induced current in the loop is:

1. clockwise

2. anticlockwise

3. zero

4. depends upon the rate at which the field is changing

Q.

When the electric current through the fuse exceeds a certain limit, the fuse wire melts and breaks.

1. True
2. False

Q.

Short circuit occurs

1. When a live wire comes in contact with an earthing wire and the resistance of the circuit falls drastically

2. When a live wire comes in contact with a neutral wire and the resistance of the circuit increases drastically

3. When a live wire comes in contact with a neutral wire and the resistance of the circuit falls drastically

4. When a neutral wire comes in contact with an earthing wire and the resistance of the circuit increases drastically

5. When a neutral wire comes in contact with an earthing wire and the resistance of the circuit falls drastically

Q. Why is the AC supply in multiple of 11 like 110V, 220V etc?

Q.

When the live and neutral wires melt and come in contact with each other , it is said that both , the live and neutral , wires carry current to the appliance , Why? If the live is connected to the neutral , the current should pass directly through the neutral wire and never reach the appliance ?

Q. What is overloading?

Q.

Fuse wire used in power circuit is of

1. 220 A

2. 10 A

3. 15 A

4. 5 A

Q. How can overloading occur in a circuit when many appliances are connected to a single socket?

Q.

Complete the following sentences :

(a) A fuse is a short piece of wire of high ___ and of the material of low ___.

(b) A fuse wire is made of an alloy of ___ and ___ if the current in a circuit exceeds the current rating of the fuse wire, it ___.

(c) A fuse is connected in ___ with the ___ wire.

(d) Higher the current rating, ___ is the fuse wire.

Q.

Why does a short circuit damage electro wiring and devices connected to it?

Q. Which of the following are the characteristics of a fuse wire?

1. Low melting point
2. Connected in parallel in a circuit
3. Safety device
4. Circuit breaker

Q.

There are two separate circuits which deliver power to our homes. Explain.

Q.

When a circuit is connected in series, if one appliance stops working other appliance connected in series also stop working

1. True
2. False

Q.

In a series combination, all appliances work independently of each other.

1. True
2. False

Q.

Is Critical Path the Longest or Shortest?

Q.

What is the purpose of a switch in a circuit? Why is the switch put in the live wire? What precaution do you take while handling a switch?

Q. Should fuse have low resistance or high.Give reason

Q. What do you mean by short-circuiting of a circuit?

Q. When does an electric short-circuit occur?

Q.

Define overloading.

Q. In a ring system, all the appliances receive the same voltage. But each appliance has a different voltage. What controls this?

Q. What is heating effect of electric current?

Q. How can overloading be avoided ?

1. By increasing number of appliances working simultaneously in circuit
2. By decreasing number of appliances working simultaneously in circuit
3. By underloading the applinces
4. By adding extra control resistors in series to the complete circuit

Q. At the time of short circuit, the current in the circuit.

1. does not change
2. keeps on increasing and decreasing continuously
3. decreases considerably
4. increases heavily