Question

If a brass bar is placed on a vibrating magnet, then its time period
A. Decreases
B. Increases
C. Remains unchanged
D. First increases then decreases

Answer 1

Hint: The length of time it takes for something to complete one oscillation is known as its time period. Normally, we can calculate frequency from angular velocity, and once we have calculated frequency, the inverse of that frequency provides us the time period. If an object is moving harmonically, we first determine the restoring force and then calculate the time period from that.

Complete step by step solution:
A brass bar's time period lengthens if it is put on a vibrating magnet because its moment of inertia grows. The term "moment of inertia" refers to the quantity that describes how a body resists angular acceleration and is calculated by multiplying each particle's mass by its square of distance from the rotational axis.

Alternatively, it can be explained in more straightforward terms as a quantity that determines the amount of torque required for a particular angular acceleration in a rotational axis. The moment of inertia is also known as the angular mass or rotational inertia. Moment of inertia definitions frequently allude to a certain rotational axis.

The square root of the ratio of the magnet's moment of inertia to the sum of its magnetic moment and background magnetic field determines the vibration magnetometer's time period. The magnetic fields for the configurations utilising magnets with various moments will not change.

Hence, the correct answer is option B.

Note: By balancing the moment (spinning acceleration) produced by the displacement and the moment due to the magnetic field, you may determine the oscillation's time period. This will create a harmonic oscillation and, as a result, a relationship for time.