A girl drops a ball of mass 0.40 kg0.40\text{ kg}0.40 kg. The ball falls a distance of 1.5 m1.5\text{ m}1.5 m to the ground. Ignore air resistance throughout this question. Take the acceleration of free fall ggg to be 10 m/s210\text{ m/s}^210 m/s2.
Calculate the decrease in gravitational potential energy of the ball as it falls through the 1.5 m1.5\text{ m}1.5 m.
The ball bounces off the floor and only rises to a maximum height of 0.90 m0.90\text{ m}0.90 m.
(i) Calculate the energy lost during the bounce.
Suggest one reason why energy is lost during the bounce.
On another occasion, the girl throws the ball straight down from a height of 1.5 m1.5\text{ m}1.5 m, giving it an initial kinetic energy of 12.0 J12.0\text{ J}12.0 J. Calculate the speed at which the ball hits the ground.
229 exam-style questions on CIE IGCSE Physics 1.7.1a Energy stores and energy transfers. Each one has a worked solution and a mark scheme showing where the marks go.