Understanding Pressure - Example 3

Example 3:
Two cubes made of the same material; one has sides twice as the other, lying on a table. Standing on one face, the small cube exerts a pressure M on the table. What is the pressure (in term of M) exerted by the larger cube standing on one of its faces, on the table?


For the small cube,

Surface area = x²
Volume = x³
Mass = m
Weight = mg

P= F A P= mg x 2 =M

For the big cube,
Surface area = 4x²
Volume = 8x³
Mass = 8m (Because the volume is 8 times greater)
Weight = 8mg

P= F A P= 8mg 4 x 2 ==2× mg x 2 =2M