Two statements are given-one labelled Assertion (A) and the other…

MCQ

Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
Assertion (A): The kinetic energy of a charged particle moving in a uniform magnetic field does not change. Reason (R): In a uniform magnetic field no force acts on the charge particle.

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 and R is also false.

✓

Answer

A is true but R is false.

Explanation:

When a charged particle is moving in a uniform magnetic field, it experiences a force in a direction perpendicular to its direction of motion. Due to which the speed of the charged particle remains unchanged and hence its kinetic energy remains same.

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