Question

A cubical copper block has each side 2.0 cm. It is suspended by a string and submerged in oil of density 820 kg m^-3 . Calculate the tension in the string.

(density of copper = 8920 kg m^-3)

Answer 1

Tension = True weight - upthrust due to oil

= Vρg- Vσg = V(ρ - σ)g

= (2 x 10^-2)³ x (8920 - 820) x 10 = 8 x 10^-6 x 8100 x 10