Question

A solid cylinder of mass `M = 10kg` and cross - sectional area `A = 20cm^(2)` is suspended by a spring of force contant `k = 100 N//m` and hangs partically immersed in water. Calculate the period of small oscillation of the cylinder.

Answer 1

Correct Answer - A
In such situation, upthrust also behaves like a spring force of force constant `= rhoAg`

`K_(net)` in the given situation is `(k + rho Ag)`
`:. T = 2pi sqrt ((m)/(k + rho Ag))`
` = 2pi sqrt ((10)/(100 + 1000 xx 20 xx 10^(-4) xx 10))`
` = 1.8 s`