Answer:
Force = -4N
Step-by-step explanation:
Given the following data;
Mass = 1kg
Initial Velocity = 20m/s
Distance = 50m
To find the acceleration;
We would use the third equation of motion;
Since, it comes to rest, its final velocity is zero (0).
V² = U² + 2as
Substituting into the equation, we have;
0 = 20² + 2*a*50
-400 = 100a
a = -400/100
a = -4m/s²
Now to find the force exerted
Force = mass* acceleration
Force = 1*(-4)
Force = -4N