A soft synthetic rubber ball of radius 12.5 cm is submerged to 9.2 m beneath the surface of a lake.
(a) If the bulk modulus of the rubber compound is Brubber = 8 x106Pa , what is the diameter of the ball at that depth?
(b) A similar ball of equal radius, but made of thin rubber inflated with air, is also submerged to the same depth. The bulk modulus of air is Bair = 2.5 x105Pa . What is the radius of this ball at that depth? (Ignore any effects of temperature.)