Question

A constant force acting on a body of mass 3.0 kg changes its speed from 2.0 m/s to 3.5m/s in 25 s. The direction of the motion of the body does not changes. What is the magnitude of the force?

• A. 0.40N
• B. 0.30N
• C. 0.10N
• D. 0.18N

Answer 1

The correct option is D 0.18N

Mass of the body, m = 3 kg
Initial speed of body, u = 2 m/s
Final speed of body, v = 3.5 m/s
Time, t = 25 s

Using the first equation of motion, the acceleration (a) produced in the body can be calculated as:

v = u+at
a=0.6m/s²
F=ma
=0.18N