Class 7 Electric Current And Its Effects CBSE Questions & Answers

Class 7 · Electric Current And Its Effects

This is Science Class 7 Electric Current and its Effects CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The magnet produced by using electric current is called
  • A
    Permanent magnet
  • B
    Bar magnet
  • C
    Electromagnet
    Correct
  • D
    Temporary magnet
2
A safety device that protect electrical appliances from short circuiting and overloading is called
  • A
    Live wire
  • B
    Fuse wire
    Correct
  • C
    Safety wire
  • D
    Neutral wire
3
Which of the following is no a conductor?
  • A
    Copper wire
  • B
    Glass
    Correct
  • C
    Sea water
  • D
    Graphite
4
Voltmeter is used to measure
  • A
    Current
  • B
    Resistance
  • C
    Potential difference
    Correct
  • D
    Power
5
Which of these does not allow the current to pass through it?
  • A
    Copper rod
  • B
    Bakelite rod
    Correct
  • C
    Brass rod
  • D
    Iron rod
6
Commercial unit of electrical energy is
  • A
    Kilowatt-hour
    Correct
  • B
    Joule
  • C
    Joule/s
  • D
    Kilowatt
7
The unit of resistance and resistivity are
  • A
    Joule and ohm
  • B
    Ohm-meter and volt
  • C
    Ohm-meter and ampere
  • D
    Ohm and ohm-meter
    Correct
8
Which of the appliances at your home does not run on electric current?
  • A
    Gas burner
    Correct
  • B
    Mixer grinder
  • C
    Air conditioner
  • D
    Television
9
A device that prevents or allow the current to flow through it
  • A
    Motor
  • B
    Terminal
  • C
    Switch
    Correct
  • D
    Conductor
10
Miniature circuit breaker works on _____________ effect of electric current.
  • A
    Heating
    Correct
  • B
    Electro-magnetic
  • C
    Chemical
  • D
    Magnetic
11
Resistance is the
  • A
    Passage of current
  • B
    Heat developed
  • C
    Obstruction in flow of current
    Correct
  • D
    Unit of current
12
Standard unit of current is
  • A
    Ohm
  • B
    Ampere
    Correct
  • C
    Watt
  • D
    Volt
13
Galvanometer is used in
  • A
    Detection of current
    Correct
  • B
    Measuring voltage
  • C
    Measuring current
  • D
    Detecting heat
14
Chemical effect of electric current is used in
  • A
    Rusting
  • B
    Painting
  • C
    Galvanizing
  • D
    Electroplating
    Correct
15
Ohms is the SI unit of
  • A
    Current
  • B
    Voltage
  • C
    Power
  • D
    Resistance
    Correct