Question

An object accelerates downward at a constant rate of 3.75 m/s2 while completely submerged in water. Neglect the viscosity (fluid friction) of the water. The average density of the object is ______ kg/m3. The density of water is 1000 kg/m3 and g

Answer 1

Do = density of obect Dw = density of water

Weight of object = V g Do

Weight of water = V g Dw

F = m a = V Do a = V g Do - V g Dw

Acceleration of object = mass * force on object

Do (g - a) = Dw g

Do = Dw ( 1 / (1 - a / g) = 1000 * 1 / (1 - 3.75 / 9.80) kg/m^3

Do = 1441 kg / m^3

If no acceleration then density of object = density of water