a) Assume that Superman has a mass of 100 kg and launches himself upwards with a speed of 60 m/s. What force would he apply if he spent
0.25s pushing off from the ground?

b) What is Superman's weight?

c) How many times bigger is the force he exerted (your answer to part a) compared to his weight (your answer to part b)?

c) Calculate the gravitational field strength of
Krypton. (Hint: You need to know the value of the gravitational field strength for the Earth's surface and that, when most people jump, they apply a force approximately equal to their weight.)