Newton's First and Second Laws of Motion:Question 5
A student is subjected to a reaction force of 10 N northward from a 5
kg block while pushing the block over a smooth, level surface.
Ignoring friction, what is the acceleration of the block?
Select one:
2
northward
southward
m
0.5
southward
m
0.5
northward

The drag force, fd, imposed by the surrounding air on a vehicle moving with velocity v is given by fd = cdaρv 2/2 where cd is a constant called the drag coefficient, a is the projected frontal area of the vehicle, and ρ is the air density. an automobile is moving at v = 80 kilometers per hour with cd = 0.28, a = 2.3 m2, and ρ = 1.2 kg/m3.