When there is a reduction in amplitude over every cycle of vibration, then the body is said to have _______
- Afree vibration
- Bforced vibration
- Cdamped vibrationCorrect
- Dunderdamped vibration
Solution
Concept
Damping removes energy, so the amplitude reduces in every cycle.
Step-by-step solution
1. Free vibration without damping has constant amplitude. 2. Forced vibration is caused by an external periodic force. 3. When energy is lost through friction or resistance, the amplitude reduces each cycle. 4. This is called damped vibration.
Explanation
When amplitude reduces in every cycle, energy is being lost due to damping. Such vibration is called damped vibration. Underdamped is only one type of damped vibration.
Why the other options are wrong
A: Free undamped vibration keeps constant amplitude. B: Forced vibration is defined by an external force, not by decaying amplitude. D: Underdamped is a special case of damping. The general term asked here is damped vibration.
Shortcut
Amplitude decreasing means damping.
Common mistake
Choosing underdamped. It also decays, but the general answer is damped vibration.
Correct answer: C) damped vibration