physics
posted by Liz on .
1. the applied force on a stationary object is less than the maximum force of static friction. Which of the statements are false
a) the object will move backwards
b) the actual force of static friction will be equal to the applied force
c) the object will remain stationary until the applied force exceeds the maximum force of static friction
d) no kinetic friction involved
2. in projectile motion, how does the total time of flight compare to the time taken to reach the maximum height?
a) time to reach max height is half the total time
b) time to reach the max height is more than half the total time
c) time to reach the max height is less than half the total time
d) depends on the total vertical change in height

Now wait a minute.
If friction wins, you do not move it in any direction.
Again in number two, imagine.
If you caught the ball at the top, the time is all spent getting up. If you tossed the ball off your roof, most of the time would be spent going down. So d)
Time to reach max is half of total indeed when begin and end are at the same height.