Answer: 34 N
Explanation:
Given
The body moved 2.25 m in 3 sec with the help of propulsion force.
Mass of body m=68 kg
Using the equation of motion
[tex]s=ut+\frac{1}{2}at^2\\\\2.25=0+\frac{1}{2}a\cdot 3^2\\\\a=0.5\ m/s^2[/tex]
Force is given by the product of mass and acceleration
[tex]F=m\times a\\F=68\times 0.5\\F=34\ N[/tex]