Question

a cube at 0°c has a length of 0.040m with a density of 920kg/m^3. Calculate the mass of ice.​

Answer 1

Answer:

The volume of the ice cube is 0.001 m

3

so the mass of the ice is 0.001×900=0.9kg

So when after melting, the Ice become water the volume will be

1000

0.9

=0.0009kg

So the excess volume of the cube that was above the water is 0.001−0.0009 = 0.0001m

3

after the ice becomes water it will fit into the volume that was inside the water and hence the change in the potential energy will for the portion that was outside the water. The height of the portion is

0.001

0.0001

=0.01m

Now the potential energy for a rectangular slab of height h and area A is P=Aρg

2

h

2

Putting the values of the parameter we get P=0.001×900×9.8×

2

0.01

2

=0.0045

Hence potential energy will be reduced by 0.0045J