MCQEasy1 mark
1
Choose the correct answers to the questions from the given options. (Do not copy the questions, write the correct answers only.)
A conductor AB is kept along north south direction of the earth above a magnetic needle as shown below. When the key K is closed then: (a) the needle will not show any deflection. (b) the needle will deflect towards east. (c) the needle will turn in the opposite direction i.e. towards south. (d) the needle will deflect towards west.
Topic: Magnetic effect of current / electromagnetic induction
Previous-year question practice database
Try it
Pick an option and check your answer. The full worked answer is below either way.
Answer
Exam answer
(b) the needle will deflect towards east.
Explanation
Using the right-hand thumb rule for current A to B, the field at the needle is eastward.
More from Electromagnetism
The diagram below shows the top view of the Wire A shown by a cross (X), carrying current into the plane of the paper. Which of the compasses is correctly aligned with the magnetic field produced by the current carrying wire?
(a) Only 1 is aligned
(b) Only 2 is aligned
(c) Both 1 and 2 are aligned
(d) Both 1 and 2 are not aligned2026intensifies the magnetic field.2026maintains electrical contact between the rotating parts and the external circuit.2026in the direction of the motion of the magnet?2026in the opposite direction of the motion of the magnet?2026The following figure shows a small bar magnet falling freely through a copper ring. For the observer at A, the direction of the induced current will be :
(a) clockwise when magnet is above and below the ring
(b) anticlockwise when magnet is above and below the ring
(c) anticlockwise when magnet is above the ring and clockwise when the magnet is below the ring
(d) clockwise when magnet is above the ring and anticlockwise when the magnet is below the ring2025