1. Which way does friction pull?
  2. Which direction does the normal force point?
  3. What does Newton’s First Law (the law of the inertia) state?
  4. Does the law of inertia apply to objects at rest or objects in motion?
  5. How much force do you need to keep an object moving in space if it’s already moving?
  6. What does ripping a piece of paper of from underneath a water bottle have to do with inertia?
  7. What would the net force be for an object moving at constant speed?
  8. Why does friction happen between surfaces? (Hint: explain zoomed in image causing friction)
  9. Which object has more inertia: a skateboarder or a semi-truck? Why?
  10. Would the mass of an object change if that object was taken to the moon? Would the weight change?
  11. If a box weighs 120 N, how much mass does the box have?
  12. What produces acceleration of any object?
  13. How are acceleration and mass related?
  14. How are acceleration and force related?
  15. A 20 kg ball and a 5 kg ball are dropped on the moon. Which one hits the ground first?  Which one has a stronger force of gravity?
  16. Suppose the force of friction on a sliding object is 35 N. What forward force is needed to maintain a constant velocity?
  17. If a wagon is pushed with 40 N and has a mass of 8 kg, what’s the acceleration it experiences?
  18. A rock is in freefall. Draw a freebody diagram.
  19. A box is dragged with an 800 N force to the right, and it has a mass of 50 kg. It only accelerates at 5 m/s/s.  What must the frictional force be?
  20. A tennis ball and a solid steel ball of the same size are dropped at the same time. In the absence of air resistance, which ball experiences a greater acceleration?
  21. What the reaction to the following statement? You push your friend with 120 Newtons to the right.
  22. If a model rocket ship weighs 200 N, and it pushes gas down with 300 N, what would be the upward force on the rocket? What is the net force on the rocket?
  23. A bug flies into a truck with a force of 4 N. The bug has a mass of 1.5 kg and the truck has a mass of 6000 kg.  What’s the acceleration of the bug?  What’s the acceleration of the truck?
  24. Draw a freebody diagram for a figure skater on ice.
  25. What does Newton’s Third Law state?
  26. Which situation is more dangerous? A car crashing into a brick wall at 100 mph or two cars crashing into each other at 50 mph. Why? (Think Newton’s Third Law…)
  27. If a 250 g mass is hanging from a pulley and attached to a 300 g, what would be the system acceleration?
  28. How much does a 850 gram object weigh?
  29. The net force on a box is 60 N left. Someone is pushing the box with 100 N left, and his friend (Joe) is pushing the box with a force to right.  How much force is Joe pushing with to the right?
  30. How can you tell if the normal force is acting on an object?