A 10cm x 10cm x 10cm wood block with a density of 700 kg/m^3 floats in water.

A 10cm x 10cm x 10cm wood block with a density of 700 kg/m^3 floats in water.

What is the distance from the top of the block to the water in cm if the water is fresh, what if it is sea water?

1 answer

The correct answer for A 10cm x 10cm x 10cm wood block with a density of 700 kg/m^3 floats in water.

density of fresh water is ρ_water = 1000 kg/m³

ΣF = 0

- (ρ_wood)g(V_wood) + (ρ_water)g(v_wood) = 0

(v_wood)/(V_wood) = (ρ_wood)/(ρ_water)

(10 * 10 * h)/(10 * 10 * 10) = (700)/(1000)

h = 7 cm

the distance from the top of the block to the water is 10 - 7 = 3 cm