Tag: effects of electric current

Questions Related to effects of electric current

State whether given statement is True or False.
We must not touch electric switches with bare hands.

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. True

  2. False

Show answer
Correct Option: A
Explanation:

It is not in general sense, but for protection purpose from any kind of defect in the insulator material damage in the electrical switch we must not touch it withh bare hands specially in case our hands are wet.

Find odd man out.
Water heater, Electric kettle, Electric iron, Electric fuse

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. Water Heater

  2. Electric kettle

  3. Electric fuse

  4. Electric Iron

Show answer
Correct Option: C
Explanation:

It is a safety device, rest are electrical appliances.

A person may get a severe electric shock on touching a :

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. a neutral wire

  2. a live wire

  3. an earth wire

  4. none of these

Show answer
Correct Option: B
Explanation:

A person may get a severe electric shock on touching the live wire. Because live wires have high potential and current flows through our body (low potential ). Thus we get electric shocks.

Wires used in homes are usually covered with materials like plastic or rubber. The primary reason for doing this is to :

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. prevent rusting

  2. make handling easier

  3. prevent shocks & short circuits

  4. make them look beautiful

Show answer
Correct Option: C
Explanation:
Wires used in homes are usually covered with materials like plastic or rubber, because plastic and rubber are bad conductors of electricity and do not allow current to flow. This prevents us from getting a shock due to a  short circuit.
Find odd man out
Electric cell, Storage cell, Electric geyser, Electric generator.
physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. Electric Cell

  2. Storage Cell

  3. Electric geyser

  4. Electric Generator

Show answer
Correct Option: C
Explanation:

Electric geyser is an appliance, rest all are sources of electricity.

Find odd one out.
Water heater, Electric iron, Electric toaster, Tube light.

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. Tube light

  2. Water heater

  3. Electric iron

  4. Electric toaser

Show answer
Correct Option: A
Explanation:

Tube light converts electric energy into light energy. Rest all produce heat.

Alternating current produced in india has a frequency of _______.

physics effects of electric current precaution with the electrical circuit precautions to be taken while dealing with current devices used to protect from shock of electric current

  1. 220 Hz

  2. 120 Hz

  3. 15 Hz

  4. 50 Hz

Show answer
Correct Option: D
Explanation:

Alternating current produced in india has a frequency of 50 Hz. i.e. the coil is rotated at the role of 50 revolution per second.

For a heater rated at 4.4 kW; 220 V  . Calculate  the energy consumed by the heater in 4 hours? 

physics effects of electric current thermal effect of electric current heating effect of electric current electric current and its effects

  1. 12 kWh

  2. 17.6 kWh

  3. 0 kWh

  4. 4.4 kWh

Show answer
Correct Option: B
Explanation:

Given :   $P = 4.4$ kW             $t = 4$ h

$\therefore$ Energy consumed in 4 h       $E= Pt =4.4\times 4 = 17.6$ kWh

How much units of energy is consumed in operating ten 50 watt bulbs for 10 hours per day in a month (30 days)

physics effects of electric current thermal effect of electric current heating effect of electric current electric current and its effects

  1. 100 kwh

  2. 150 kwh

  3. 160 kwh

  4. 500 kwh

Show answer
Correct Option: B
Explanation:
Given :    $P = 0.05$ kW               $t = 10$ hours per day 
Number of bulbs     $n = 10$
Energy consumed per day       $E= nPt = 10 \times 0.05\times 10 = 5$ kwh  per day
Total energy consumed in 30 days    $E _t = 5\times 30 = 150$ kWh

Which of the following is true for electrical energy?

physics effects of electric current thermal effect of electric current heating effect of electric current electric current and its effects

  1. $E = P \times t$

  2. $E = \dfrac{P}{t}$

  3. $E = \dfrac{{V}^{2}}{Rt}$

  4. None of these

Show answer
Correct Option: A
Explanation:

Electrical energy consumed by an electric appliance is equal to product of its power rating and time for which it is used $E = P \times t$.