If the car's speed decreases at a constant rate from 77 mi/h to 50 mi/h in 3.0 s, what is the magnitude of its acceleration, assuming that it continues to move in a straight line?

The acceleration of the car,

Here, v is final velocity, u is initial velocity and t is time taken by the car.

Given , and

Therefore, from above equation

.

Here, negative sign shows deceleration of a car.

Thus the the magnitude of car acceleration is .

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.