Tag: household circuits

Questions Related to household circuits

In an household electric circuit, which of the following is/are correct?
(A) All electric appliances drawing power are joined in parallel.
(B) A switch may be either in series or in parallel with the appliance which it controls.
(C) If a switch is in parallel with an appliance, it will draw power when the switch is in the 'off' position (open).
(D) If a switch is in parallel with an appliance, the fuse will blow (burn out) when the switch is put 'on' closed.

physics household circuits electric switch switch electrical circuit

  1. A, D

  2. A, C, D

  3. B, C, D

  4. A, B, D

Show answer
Correct Option: B
Explanation:

In the household if the appliances are connected in series, if one appliance is turned off then the whole circuit breaks and all other will get turned off. So they are always connected in parallel so that we can use appliances independent of other.
The switch of an appliance must be connected in series because the purpose of a switch is to turn off/on (break and connect the circuit). So when we connect the switch in series, the appliance turn's on when switch is closed and off when open.
If the switch is connected in parallel, even when it is off(open) the appliance draws power and when it is on the terminals of the appliance gets shorted and blows the fuse.

State whether true or false.
A switch is used to close or open an electric circuit.

physics household circuits electric switch switch electrical circuit

  1. True

  2. False

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Correct Option: A
Explanation:

A switch is a device that is used to  open or close a circuit to control the flow of current in a circuit.


Given statement is $True$.

Switches of the electric appliances are connected in the _____ wire.

physics household circuits electric switch switch electrical circuit

  1. neutral

  2. line

  3. earth

  4. all

Show answer
Correct Option: B
Explanation:

Each local circuit in a room is provided with a seperate switcho switches are connected in the live wire, so that when the switch is in the off portion, no point of the connected electric appliance will be at higher potential.

In a household electric circuit:

physics household circuits electric switch switch electrical circuit

  1. all electric appliances drawing power are joined in parallel

  2. a switch may be either in series or in parallel with the appliance which it controls

  3. if a switch is in parallel with an appliance, it will draw power when the switch in the off position (open)

  4. if a switch is in parallel with an appliance, the fuse will blow (burn out) when the switch is put on (closed)

Show answer
Correct Option: A,C,D
Explanation:

All appliances in houses are connected parallel so that even if one get damaged , others will work properly and all appliances are independent .
If switch is connected in parallel, there will be short circuit when  switch is on and hence fuse will be blown and when switch is off, the appliance will draw power and there won't be any short circuit.

Of the three connecting wires in a household circuit : (i) Which of the three wires should the switch be connected ?

physics household circuits electric switch switch electrical circuit

  1. Live

  2. Neutral

  3. Earth

  4. All of these

Show answer
Correct Option: A
Explanation:

Switch must be connected to the live wire so that it can disconnect the circuit when it is switched off.

State whether true or false.
Electricity used at homes is generated in powerhouses.

power transmission household electricity household circuits electricity and magnetism physics

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

Electricity used in homes is made at a power plant by huge generators. Most power plants use coal, but some use natural gas, water or even wind.

State whether true or false.
Electricity used in homes is generated from storage cells.

power transmission household electricity household circuits electricity and magnetism physics

  1. True

  2. False

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Correct Option: B
Explanation:

Electricity used in homes is made at a power plant by huge generators. Most power plants use coal, but some use natural gas, water or even wind.

An electric fan marked 60 watt consumes 3 units for the duration:

power transmission household electricity household circuits electricity and magnetism physics

  1. 50 hours

  2. 150 hours

  3. 10 hours

  4. 15 hours

Show answer
Correct Option: A
Explanation:

Answer is A.

The total energy consumed is 3 units = 3 kWh = 3000 Wh.
The total enrgy dissipated is given as Power * Time.
Therefore, time = Energy dissipated / Power.
Time taken = 3000 Wh / 60 W = 50 hours.
Hence, an electric fan marked 60 watt consumes 3 units for the duration of 50 hours.

Electricity generated at power station is

power transmission household electricity household circuits electricity and magnetism physics

  1. AC

  2. DC

  3. Both of these

  4. None of these

Show answer
Correct Option: A
Explanation:

Electricity generated at power station is AC usually $11  KV$ to $22  KV$.

The cost of electricity for domestic use is Rs.$2.30$ per unit. This unit is:

power transmission household electricity household circuits electricity and magnetism physics

  1. $1$ Ampere

  2. $1$ Volt

  3. $1$ Joule

  4. $1$ Kilo-Watt-hour

Show answer
Correct Option: D
Explanation:

The unit of electricity for domestic use is 'KWh'(KiloWatt-hour)