A 120 kg car is travelling at a velocity of 20m/s East when its brakes are locked. Assuming a force of friction of 2500 N, what is the velocity of the car after 0.50s.
To find the velocity of the car after 0.50s, we need to consider the forces acting on the car and apply Newton's second law of motion.
Newton's second law states that the net force acting on an object is equal to the mass of the object multiplied by its acceleration. In this case, the net force is the force of friction opposing the motion of the car.
The formula for calculating acceleration is:
acceleration = net force / mass
Given:
Force of friction (F) = 2500 N
Mass (m) = 120 kg
We can substitute these values into the formula to find the acceleration:
acceleration = F / m
acceleration = 2500 N / 120 kg
Simplifying this calculation, we get:
acceleration = 20.83 m/s²
Now, let's use this acceleration and the initial velocity of 20 m/s to find the final velocity (Vf) after 0.50s using the following kinematic equation:
Vf = Vi + (acceleration * time)
Given:
Initial velocity (Vi) = 20 m/s
Time (t) = 0.50 s
Substituting the values into the equation, we get:
Vf = 20 m/s + (20.83 m/s² * 0.50 s)
Calculating this, we get:
Vf = 20 m/s + 10.415 m/s
Therefore, the velocity of the car after 0.50s when its brakes are locked is:
Vf = 30.415 m/s East