Question

An aluminum bar has a mass of 9 kg in the air. Calculate its volume. Now imagine that you submerge the aluminum bar in water hanging it from a rope. Calculate the apparent weight it would have in the water.

Answer 1

55.7 N

Step-by-step explanation:

The density of aluminum is 2710 kg/m³. So its volume is:

V = (9 kg) / (2710 kg/m³)

V = 0.00332 m³

The apparent weight is the actual weight minus the buoyant force.

N = mg − B

N = mg − ρVg

N = g (m − ρV)

N = (9.8 m/s²) (9 kg − (1000 kg/m³) (0.0332 m³))

N = 55.7 N