F = force applied to stop the car = - 3000 N
m = mass of the car = 3000 kg
a = acceleration of the car = ?
v₀ = initial velocity of the car before the force is applied to stop it = 10 m/s
v = final velocity of the car when it comes to stop = 0 m/s
d = stopping distance of the car
acceleration of the car is given as
a = F/m
inserting the values
a = - 3000/3000
a = - 1 m/s²
using the kinematics equation
v² = v²₀ + 2 a d
inserting the values
0² = 10² + 2 (-1) d
0 = 100 - 2 d
2 d = 100
d = 100/2
d = 50 m
hence the correct choice is
C. 50 m