Question

Questlon 7 of 10

Which object will require the greatest amount of force to change its motion?
O A. A 72 kg object moving 25 m/s
O B. A 55 kg object moving 32 m/s
OC. A 75 kg object moving 22 m/s
O D. A 63 kg object moving 27 m/s

Answer 1

A 72 kg object moving 25 m/s will require the greatest amount of force

Further explanation

Given

mass of object and the velocity

Required

the greatest amount of force

Solution

Newton's 2nd law :

∑F = m. a

F = force, N

m = mass = kg

a = acceleration due to gravity, m / s²

Assuming the object is moving from rest (vo = 0) and the time needed to reach its velocity is the same (delta t = equal), it can be formulated:

`\tt \Sum F=m.(v_f-v_i)/(\Delta t)\\\\F=m.(v_f)/(\Delta t)`

So the force on an object depends on the product of its mass and velocity

Or if we use the impulse and momentum formula

`\tt F.\Delta t=m(v_f-v_i)\\\\F,\approx m.v_f`

So that we determine which is the greatest from the multiplication of mass and velocity will produce the greatest force as well

A 72 x 25 = 1800

B. 55 x 32 =1760

C. 75 x 22 = 1650

D.63 x 27 = 1701

Option A has the greatest force