1 Frictional force is the force that opposes the motion of an object and which acts parallel to the surface.
2 Newton's Third law: When object A exerts a force on object B, object B simultaneously exerts an oppositely directed force of equal magnitude on object A.
3a Fnet = ma
Fengine – f – T = 0
9 000 – 0,45(Fg) – T = 0
9 000– 0,45(1 300)(9,8) – T = 0
T = 3 267 N
b. Fnet = ma
T – f = 0
3 267 – f = 0
f = 3 267 N (backwards)
fk = μkN
fk = μkmg
3 267 = μk(950)(9,8)
μk = 0,35
4. According to Newton's first law, an object will continue moving at a constant velocity unless a non-zero net force acts on it. The net force acting on the car now is the frictional force and it causes the car to slow down.
5. Fnet = ma
-3 267 = 950a
a = -3,44 m∙s-2
= 3,44 m∙s-2 backwards or to the right