Question

a 3.5 kg mass has an initial velocity of 4.0 m/s. How much force is required to increase the velocity of the mass to 8.0 m/s in 3.0 seconds?

Answer 1

4.67 N of force are required

Step-by-step explanation:

The second Newton's law states the net force exerted on a body of mass m that has an acceleration a, is given by:

F=m.a

On the other hand, the kinematics equations relate the acceleration with the change of speed over time, expressed as:

`\displaystyle a=(v_f-v_o)/(t)`

We are given the initial speed of vo=4 m/s on a mass of m=3.5 Kg, the final speed of vf=8 m/s which took t=3 seconds.

The acceleration is:

`\displaystyle a=(8-4)/(3)=1.33`

`a=1.33\ m/s^2`

Thus, the force is:

`F=3.5\ Kg\cdot 1.33\ m/s^2`

`F=4.67\ N`

4.67 N of force are required