A body of density `rho` is dropped from rest from height h (from the surface of water) into a lake of density of water `sigma(sigmagt rho)`. Neglecting all disspative effects, the acceleration of body while it is in the take is

Options

A. `g((sigma)/(rho)-1)` upwards
B. `g((sigma)/(rho)-1)` downwards
C. `g((sigma)/(rho))` upwards
D. `g((sigma)/(rho))` downwards

Answer

A

Explanation

`a=("upthrust-weight")/("mass")`(upwards)
`=(Vsigma g-V rho g)/(V rho)=((sigma)/(rho)-1)g` (upward).