Question

a 40 kg rock lies at a bottom of a lake. The volume of water it displaces is 800cm³. Calculate the minimum force required to lift the rock from the bottom of the lake.​

Answer 1

384.6 N

Step-by-step explanation:

The rock is buoyed up by a force of the water it displaces

800 cm^3 of water is 800 gm

the force required to lift the rock will then be

40 kg - 800 gm = 39.2 kg

F = ma = 39.2 * 9.81 = 384.6 N