Question

what is the force required to accelerate a 4kg rock from 3 m/s to 15 m/s in 3 seconds?​

Answer 1

To calculate the force required to move a 4 x 10^3 gram rock from 3 to 15 m/s in 3 seconds, first find the a value acceleration and then from there calculate what the force is by using F = ma

Vf = Vi + at
15 = 3 + 3a
12 = 3a
a = 4 m/s^2

F= 4 • 4 = 16 kgm/s^2.

This is the total force.

Answer 2

Answer:

Force required is 16 N.

Explanation:

By Newton's second law of motion,

F = ma

where F is the force,m is mass and a is acceleration.

Given:

initial speed = u = 3 m/s.

final speed = v = 15 m/s

time taken = t = 3 s

acceleration = a = $\frac{v-u}{t}=\frac{15-3}{3}=4\ ms^{-2}$

mass of the rock = 4 kg

Force = mass*acceleration = 4*4 = 16 N.