6. The figure shows a student pushing a 1.22 kg box across a frictionless floor a distance of 5.0 m by applying a force of 30.0 N.
What is the work done on the box by the two forces, Fn and Fa , as it
is pushed 5.0 m along the floor?
F = 12.0 N
F=30.0 N
5 m
A. Work by Fn = 0 Joules Work by Fa = 0 Joules
B. Work by Fn = 0 Joules Work by Fa = 150 Joules
C. Work by Fn = 60 Joules Work by Fa = 0 Joules
D. Work by Fn = 60 Joules Work by Fa = 150 Joules

You are driving to the grocery store at 20 m/s. you are 110m from an intersection when the traffic light turns red. assume that your reaction time is 0.50s and that your car brakes with constant acceleration. how far are you from the intersection when you begin to apply the brakes? what acceleration will bring you to rest right at the intersection? how long does it take you to stop after the light changes? the known values: vi=20m/s xi=110m t=.50s vf=0m/s xf=0m a=?