Question

If a force of 30.6 kg act on 60 kg mass calculate the resulting accleration

Answer 1

Explanation:

F = 30.6N , newton is the unit of force not kg, so probably its 30.6N

m = 60

F = ma

becomes a = F/m = 30.6/60 = 0.51 m/s²

Answer 2

Answer:

An 850-kg car is accelerating at a rate of 2.4m/s2 to the right along a straight and horizontal road where it experiences an overall frictional force of 1500N.  Determine the force that its engine exerts.

Explanation:

Solution:  If  "to the right"  is taken to be positive as usual, Fe is positive, and Ff negative.  Note that friction always opposes the direction of pending motion.  Applying Newton's 2nd law:

ΣF = Ma    ;    Fe - Ff  =  Ma    ;    Fe - 1500N  =  (850kg)(2.4m/s2)    ;    Fe  = 1500N  +  2040N  =  3500N

Note that the 2040N must be rounded to 2 significant figures and then added to the 1500N.