Question

Assertion (A): The energy of a charged particle moving in a magnetic field does not change. % Reason (R) Reason (R): It is because the work done by the magnetic force on the charge moving in a magnetic field is zero.

• A. If both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
• B. If both Assertion (A) and Reason (R) are true and Reason (R) is not the correct explanation of Assertion (A).
• C. If Assertion (A) is true but Reason (R) is false.
• D. If both Assertion (A) and Reason (R) are false.

Hint:

The magnetic force on a charged particle is always perpendicular to its velocity, causing no change in kinetic energy.

Answer 1

The Correct Option is A

The kinetic energy of a charged particle is conserved in a magnetic field. This is because the magnetic force, always perpendicular to the particle's velocity, performs no work. Consequently, the magnetic force does not alter the particle's kinetic energy, meaning its energy remains constant. Therefore, both the statement and the explanation are valid, with the explanation accurately supporting the statement.