19. How much force does it take to accelerate a 3.50 kg mass from 3.00 m/s to 17.0 m/s in a time of

2.0 s?

20. A 14.0 N force is applied to a 3.50 kg object at rest on a smooth table. a) How fast will it be travelling after 3.00 s? b) How long will it take to travel the first 72.0 meters?

21. A 7.00 N force is applied to a 1.75 kg object at rest on a horizontal smooth table. a) At what rate will the object accelerate? b) How fast will it be travelling after 3.0 seconds? c) How long will it take to travel the first 72 meters?

B. Problems with Friction

22. The force of friction between a surface and a stationary 5.00 kg block is 7.00 Newtons. What is the acceleration of the block when a 6.20 Newton force is applied to it?

23. A 34.0 kg object initially at rest is acted on by two forces in the opposite direction. The two forces are 28.0 N and 20.0 N respectively. If the force of friction acting on this block is 14.0 N, how fast will the block be moving after two seconds?

24. If a 3.00 kg cart moves at a constant 4.00 m/s when being pushed for 5.00 s by a force of 6.00 N, what is the force of friction acting on the cart?

25. What is the force of friction if a 3.00 N force applied to a 3.00 kg cart accelerates it at 0.750 m/s2?

26. A constant force of 15.0 Newtons is applied to a block of mass 3.00 kg on a horizontal table. If in 6.00 s the block's velocity increases from 2.00 m/s to 23.0 m/s, what is the force of friction acting on the block?

27. Two forces act on a 10.0 kg mass on a frictionless surface. One force is 20.0 N westward and the other force is 15.0 N southward.

a) Find the resultant force. b) What is the acceleration? c) How would a force of friction affect the acceleration?

28. What is the force of friction if a 3.00 kg object accelerates at 4.50 m/s2 when pulled by a 15.0 N force?

29. In the Newton's law experiment, Wendy and Kim had a cart with a mass of 1.12 kg. When they applied a force of 1.80 N to the cart they obtained an acceleration of 1.55 m/s2. Calculate the force of friction acting on their cart.

30. A 2.60 kg block was observed to increase in velocity from 2.00 m/s to 12.0 m/s in a period of 2.00 s when acted on by a force of 15.0 N. What is the force of friction acting on the block?

31. A 12.2 N force is applied to 17.0 kg mass and it accelerates at 0.500 m/s2. What is the frictional force acting?