Question

Vibrations, whose amplitude of oscillation decreases with time are called

• A. free vibrations
• B. forced vibrations
• C. damped vibrations
• D. none of these

Answer 1

The correct option is C

damped vibrations

The explanation for the correct option:

1. Any free vibrations which are affected by an external resistive force that reduces the amplitude of vibration with time, such vibrations are called Damped vibrations.
2. For example- A ball swinging freely from a thread fixed at some point, the air resistance works as a resistive force which dampens or reduced the amplitude of vibration of a ball with time, such vibration is an example of Damped vibrations.
3. Therefore, Vibrations, whose amplitude of oscillation decreases with time are called damped vibrations.

The explanation for the incorrect options:

1. When an initial input as a force is given to a system which results in motion of the system as vibration and later this system vibrates freely without the help of any external force can be termed as free vibrations.
2. Forced vibration is the tendency of one object to force another adjoining or interconnected object into vibration motion.

Hence, option (c) is correct.