Question

A metal ball weighs 34.5 N in air and 24.3 N when it is immersed in water. What is the radius of the ball?

Answer 1

Gravitational acceleration = g = 9.81 m/s²

Density of water = = 1000 kg/m³

Weight of the metal ball in air = W = 34.5 N

Volume of the metal ball = V

Weight of the metal ball in water = W_a = 24.3 N

Buoyancy force from the water on the metal ball = F = Vg

W = W_a + F

W = W_a + Vg

34.5 = 24.3 + (1000)(9.81)V

V = 1.04 x 10^-3 m³

Radius of the ball = R

R = 6.285 x 10^-2 m

Radius of the ball = 6.285 x 10^-2 m