Question

A body floats in a liquid contained in a beaker. The whole system as shown falls freely under gravity. The upthrust on the body due to the liquid is

• A. Zero
• B. Equal to the weight of the liquid displaced
• C. Equal to the weight of the body in air
• D. Equal to the weight of the immersed position of the body

Answer 1

Answer: (A)

Zero

Answer 2

Upthrust $= V \rho _ { \text {liquid } } ( g - a )$; where, a = downward acceleration,

V = volume of liquid displaced

But for free fall a = g

$\therefore$ Upthrust = 0