1. What is the difference between mass and weight? Does one of these matter more than the other when you are dieting, or are both important? Why?
2. What is frictional force? Name at least two examples from everyday life where friction is important, and explain why
3. Training astronauts for weightlessness is always a challenge for NASA to simulate or for theme park rides to achieve. Name at least one method which can be used to simulate weightlessness and describe in detail the forces involved and how they counteract the force of gravity.