A 1000-kg car moving at 10 m/s brakes to a stop in 5 s. The average braking force is? On this question I asked my teacher I am suppose to get 2000 N and I don't get how to get it.
To calculate the average braking force, we can use the equation for force:
Force = Mass x Acceleration
In this case, the car is braking to a stop, so the final velocity (vf) is 0 m/s. We can calculate the acceleration (a) using the following formula:
vf = vi + at
Where:
- vf is the final velocity (0 m/s),
- vi is the initial velocity (10 m/s),
- a is the acceleration, and
- t is the time taken to stop (5 seconds).
Rearranging the formula, we find:
a = (vf - vi) / t
Substituting the given values:
a = (0 m/s - 10 m/s) / 5 s
a = -10 m/s / 5 s
a = -2 m/s^2
Note that the negative sign indicates deceleration (in the opposite direction of motion).
Now, we can calculate the average braking force by substituting the mass (m) and the acceleration (a) into the force equation:
Force = Mass x Acceleration
Force = 1000 kg x (-2 m/s^2)
Force = -2000 N
The negative sign means that the force is in the opposite direction of motion. However, in the context of this question, we are only concerned with the magnitude (absolute value) of the force, so the average braking force is 2000 N (not -2000 N).