Question #b7a84

1 Answer
Dec 2, 2015

Answer:

#F=480 N#

Explanation:

The special case of Newton's second law of motion relates resultant force and acceleration:
#F=ma#

The question specifies that the acceleration is uniform, so we can use the equations of uniform acceleration to determine the value of #a# for #F=ma#

Stage 1: Determine which "suvat" equation to use.
List all values we know:
#s: 32 m#
#u: 0 m s^(-1)#
#v: × #
#a:?#
#t: 12.0 s#

So we need.to use the equation that does not have #v# in it, i.e. #s=ut +½ at^2#

Rearrange for the unknown, #a# (u=0 so ut=0), and substitute cakes into the equation. 
#s=½ at^2 ⇒ a=2s/t^2=(2 × 32) / 12^2 = 0.4444 m s^(-2)#

Stage 2 : Use that acceleration to calculate the force.
The mass of the pachyderm is given as 1080 kg.
#F=ma=1080×0.4444= 479.952 N #

To 3 s.f that is # F = 480 N #