There are six books in a stack, each with a weight of 3.0 N. The coefficient of friction between all the books is 0.20 as is the coefficient between the table and the bottom book. What horizontal push must I just exceed on the next to bottom book to start sliding the top five books off the bottom one?
a. 1.0 N
c. 3.0 N
b. 5.0 N
d. 7.0 N
Question 2
As a car skids with its wheels locked trying to stop on a road covered with ice and snow, the force of friction between the icy road and the tires will usually be:
a. greater than the normal force of the road times the coefficient of static friction.
b. equal to the normal force of the road times the coefficient of static friction.
c. less than the normal force of the road times the coefficient of static friction.
d. greater than the normal force of the road times the coefficient of kinetic friction.