A box with a mass of 2 kg accelerates in a straight line

from 4 m/s to 8 m/s due to the application of a force

whose duration is 0.5 s. Find the average strength of this

force.

Answer: 16N

Explanation:

Given that:

mass of box M = 2 kg

Initial speed V1 = 4 m/s

Final speed V2 = 8 m/s

Time taken T = 0.5 s

Average strength of this force F = ?

Now, recall that Force is the rate of change of momentum per unit time

i. e Force = momentum / time

Hence, F = M x (V2 - V1) / T

F = 2kg x (8 m/s - 4 m/s) / 0.5s

F = 2kg x (4 m/s / 0.5s)

F = 2kg x 8 m/s/s)

F = 16N

Thus, the average strength of this

force is 16 newton.