Answer:
4.67 N of force are required
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:
[tex]\displaystyle a=\frac{v_f-v_o}{t}[/tex]
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:
[tex]\displaystyle a=\frac{8-4}{3}=1.33[/tex]
[tex]a=1.33\ m/s^2[/tex]
Thus, the force is:
[tex]F=3.5\ Kg\cdot 1.33\ m/s^2[/tex]
[tex]F=4.67\ N[/tex]
4.67 N of force are required
