Speed of 90 km/h when expressed in m/s is:5 m/s 25 m/s 250 m/s 2,500 m/s Not enough information is given 8. An object of mass m accelerates at a...

5. Speed of 90 km/h when expressed in m/s is:

1. 2.5 m/s
2. 25 m/s
3. 250 m/s
4. 2,500 m/s
5. Not enough information is given 

8. An object of mass m accelerates at a rate of a when the force of F acts on it. If the mass is increased to 3m, the resulting acceleration will be:

1. a/3
2. a/2
3. a
4. 2a
5. 3a 

9. Static friction occurs

1. When the object is moving
2. When the object is stopped, and the upper limit cannot be overcome
3. When the object is slipping, and moving to the right
4. When you overcome the upper limit, and the object is not at rest
5. It doesn't occur, and we simply consider kinetic friction 

10. Kinetic friction happens when

1. The static friction is overcome, and object changes from stationary to moving
2. Static friction is not overcome, object is at rest
3. Object is stationary, and there is no static fri ction
4. Object is not slippery, and will come to rest
5. None of the above