Practicing Class 8 Science MCQ and Class 8 Science Chapter 4 Electricity: Magnetic and Heating Effects MCQ Questions Online Test with Answers daily helps in time management.
Class 8 Electricity: Magnetic and Heating Effects MCQ with Answers
MCQ on Electricity: Magnetic and Heating Effects Class 8
Class 8 Science Chapter 4 Electricity: Magnetic and Heating Effects MCQ Questions with Answers
Question 1.
What happens to the compass needle when the switch is turned ‘ON’ and an electric current flows through the wire?
(a) The needle disappears
(b) The needle points to the south
(c) The needle deflects from its original position
(d) The needle breaks
Answer:
(c) The needle deflects from its original position
Question 2.
Which household appliance does not work on the heating effect of electric current?
(a) Electric iron
(b) Electric bulb
(c) Hair dryer
(d) Electric fan
Answer:
(d) Electric fan
Question 3.
What is the effect of inserting an iron nail into the cylindrical coil?
(a) It blocks the current
(b) It weakens the magnetic field
(c) It turns the coil into a permanent magnet
(d) It strengthens the magnetic field of the coil
Answer:
(d) It strengthens the magnetic field of the coil
Question 4.
What is an electromagnet?
(a) A permanent magnet made of iron
(b) A device that generates electricity from magnetism
(c) A current-carrying coil that behaves like a magnet
(d) A magnet used only in compasses
Answer:
(c) A current-carrying coil that behaves like a magnet
Question 5.
A Voltaic cell is also known as
(a) Electrolytic cell
(b) Dry cell
(c) Solar cell
(d) Galvanic cell
Answer:
(d) Galvanic cell
Electricity: Magnetic and Heating Effects Class 8 Assertion-Reason Type Questions
Directions (Q. No. 1 to 5): Each question below consists of an Assertion (A) and a Reason (R).
Use the following key to choose the appropriate answer.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A
(c) A is true but R is false.
(d) A is false but R is true.
Question 1.
Assertion (A): A coil with more turns produces a stronger electromagnet.
Reason (R): Increasing the number of turns increases the magnetic field produced by the current-carrying coil.
Answer:
(a) Both A and R are true and R is the correct explanation of A.
Question 2.
Assertion (A): An electric iron works on the magnetic effect of electric current.
Reason (R): Electromagnets are used in devices like electric fans and electric bells.
Answer:
(d) A is false but R is true.
Question 3.
Assertion (A): A nichrome wire gets heated when electric current flows through it.
Reason (R): Nichrome offers high resistance to the flow of electric current.
Answer:
(a) Both A and R are true and R is the correct explanation of A.
Question 4.
Assertion (A): A dry cell is preferred over a Voltaic cell for use in portable electric devices.
Reason (R): The dry cell uses a thick pastelike electrolyte and is easier to carry.
Answer:
(a) Both A and R are true and R is the correct explanation of A.
Question 5.
Assertion (A): The compass needle does not deflect when placed near a coil that is not connected to a battery.
Reason (R): A Magnetic field is produced only when current flows through the coil.
Answer:
(a) Both A and R are true and R is the correct explanation of A.
Electricity: Magnetic and Heating Effects Class 8 Fill in the blanks
Question1.
When an electric current flows through a conductor, it produces a magnetic field around it. This phenomenon is known as
……….. effect of electric current.
Answer:
magnetic
Question 2.
In an electromagnet, both the ……….. and the number of ……….. increase the strength of magnetic field.
Answer:
current, turns
Question 3.
When two magnets are brought close to each other, their ……….. poles attract.
Answer:
opposite
Question 4.
A single cell provides only a ……….. amount of current, so the magnetic field is weak.
Answer:
small
Question 5.
A nichrome wire offers higher resistance compared to ……….. wire of the same size and length.
Answer:
copper
Electricity: Magnetic and Heating Effects Class 8 True or False
Question 1.
In an LED, current flows when the positive terminal of the LED is connected to the negative terminal of the battery.
Answer:
False
Question 2.
Electric kettle works on the magnetic effect of current.
Answer:
False
Question 3.
Dry cell is a portable sources of electricity.
Answer:
True
Question 4.
Rechargeable batteries can be recharged and reused multiple times.
Answer:
True
Question 5.
A moving magnet can also lead to an electric current.
Answer:
True
Electricity: Magnetic and Heating Effects Class 8 Match the following
Question 1.
| Column A | Column B |
| (i) Zinc container | (a) Positive terminal |
| (ii) Carbon rod | (b) Electrolyte |
| (iii) Metal cap | (c) Negative terminal |
| (iv) Paste-like substance | (d) Covers the carbon rod |
Answer:
| Column A | Column B |
| (i) Zinc container | (c) Negative terminal |
| (ii) Carbon rod | (a) Positive terminal |
| (iii) Metal cap | (d) Covers the carbon rod |
| (iv) Paste-like substance | (b) Electrolyte |