Question

Bulk modulus for rubber is `9.8xx10^(8)Nm^(-2)`. To what depth should a rubber ball be taken in a lake so that its volume is decreased by `0.1%`
A. 9 m
B. 18 m
C. 180 m
D. 90 m

Answer 1

Correct Answer - D
(d) Elongation `Deltal=(FL)/(AY)=(FV)/(A^(2)Y)" "(V=AxxLimpliesL=(V)/(A))`
or `F=(A^(2)Deltal)/(V)`
`therefore F prop A^(2)`
As cross-sectional area of 2nd wire is 3 times therefore 9F force is required for same elongation .