Q. A block suspended from a spring at natural length and is free to move vertically in the -direction. Then

Work, Energy and Power Report Error

A

Mass is released when ; the maximum value of reached by the mass is

B

Mass is released when ; the maximum value of reached by the mass is

C

Duc to air resistance the mass settles down into an equilibrium position , the mechanical energy lost is

D

Due to air resistance the mass settles down into an equilibrium position , the mechanical energy lost is

Solution:

For (1):

Hence, (1) is correct, (2) is wrong.
For (3):
Let velocity on reaching is when there was no air resistance.
Then

Now this will be lost when finally mass settles down at Hence, is correct, (4) is wrong.

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