A 900-kg car is moving at 27.6 m/s. A braking force of -4320 N is applied for 4.60 s. What is the velocity of the car when the brakes are released?
Vf=Vo+at were a=force/mass
find vf
To find the final velocity of the car when the brakes are released, we can use the kinematic equation:
Vf = Vi + (a * t)
Where:
Vf is the final velocity of the car,
Vi is the initial velocity of the car,
a is the acceleration,
t is the time.
In this case, the initial velocity (Vi) is given as 27.6 m/s, and the acceleration (a) can be derived from the braking force (F) and the mass (m) of the car using Newton's second law of motion (F = m * a):
a = F / m
Given that the braking force (F) is -4320 N (negative because it opposes the car's motion), and the mass (m) is 900 kg, we can calculate the acceleration (a):
a = -4320 N / 900 kg
Finally, the time (t) is given as 4.60 s.
Now, we can substitute the given values into the kinematic equation to find the final velocity (Vf):
Vf = Vi + (a * t)
Vf = 27.6 m/s + ((-4320 N / 900 kg) * 4.60 s)
Calculating this expression will give us the final velocity of the car when the brakes are released.