Question

A piece of stone has volume 400 m² and density 7.8x10.9 kg/m3. It is immersed in water of density 1000 kg/m3. Calculate the weight of the stone in air and upthrust.​

Answer 1

Answer:

7800 kg/m^3 = 7.8 g/cm^3

so the mass is 7.8 * 400 = 3120 g

weight in air = mg = 30.6 N

in water, subtract the weight of the 400cm^3 of water