1. Period 2 Question 1

2. As a car skids with its wheels locked trying to stop on a road covered with ice the force of friction between the icy road and the tires usually will be
greater than the normal force of the road times the coefficient of static friction
equal to the normal force of the road times the coefficient of static friction
equal to the normal force of the road times the coefficient of kinetic friction
less than the normal force of the road times the coefficient of kinetic friction

3. Period 2 Question 2

4. A brick slides on a horizontal surface
A brick slides on a horizontal surface. Which of the following will increase the frictional force on it?
Putting a second brick on top
Decreasing the surface area of contact
Increasing the surface area of contact
Decreasing the mass of the brick

5. Period 3 Question 1

6. In case A a box is dragged along a horizontal surface, in case B it is dragged up an incline by a force parallel to the incline. The frictional force in case B, as compared to case A, is:
Always the same
Always greater
Always less
Less for some angles, larger for others

7. Period 3 Question 2

8. A ball is thrown downward from the edge of a cliff with an initial speed that is greater than the terminal velocity. Initially the ball’s acceleration is
upward acceleration
no net acceleration
downward, acceleration less than g
downward, acceleration greater than g