A car brakes from 60 mph to a full stop in 4 seconds. Find the accelerayion of the car during this interval
To find the acceleration of the car during this interval, we can use the formula for acceleration:
acceleration = (final velocity - initial velocity) / time
In this case, the initial velocity of the car is 60 mph and the final velocity is 0 mph (since the car comes to a full stop). The time taken for the car to brake is 4 seconds.
First, we need to convert the initial and final velocities from miles per hour (mph) to feet per second (ft/s) because the formula requires consistent units. We know that 1 mph is equal to 1.47 ft/s, so we can calculate:
initial velocity = 60 mph * 1.47 ft/s per mph = 88.2 ft/s
final velocity = 0 mph * 1.47 ft/s per mph = 0 ft/s
Now we can substitute these values into the acceleration formula:
acceleration = (final velocity - initial velocity) / time
acceleration = (0 ft/s - 88.2 ft/s) / 4 s
Simplifying the equation, we get:
acceleration = (-88.2 ft/s) / 4 s
Therefore, the acceleration of the car during this interval is -22.05 ft/s².
Note that the negative sign indicates that the acceleration is in the opposite direction of the initial velocity, which makes sense since the car is decelerating (slowing down) to a stop.