Question

Find the density of the block of wood that floats in water with 0.1 of its volume above water. (a)0.9g/cc (b)0.3g/cc (c)0.1g/cc (d)0.2g/cc

Answer 1

Answer:

The density of the block is 0.9g/cc.

Explanation:

The block has 0.1 of its part above water.                  Let volume be x.

This means the part under water is 0.9x.

Thus, the buoyant force applied by water on the block is: density of water * 0.9x * g.

The weight on the block is: mg = density of block *  x * g

Thus we know that if the block floats, then the net force is 0.

This implies, Buoyant force - mg = 0

Therefore, buoyant force = mg

Thus, density of water * 0.9x * g =  density of block *  x * g

Density of water = 1g/cm^3

Thus, solving this we get the answer as  0.9g/cc    (cm^3)

Thus, option a is right.

HOPE THIS HELPS YOU...

Answer 2

Answer:

Answer is 0.9 g/cc

Explanation:

We know that (Volume of immersed part/Volumes of solid)= (Density of solid/density of liquid).

Let volume be x and density be y.If 0.1 of the volume is floating, it means that 0.9 of it is immersed.

That is, 0.9x/x = y/1 (since density of volume is 1g/cc)

That is, 0.9 = y

Therefore, density of the solid is 0.9g/cc