Question

A state patrol officer saw a car start from rest at a highway​ on-ramp. She radioed ahead to another officer 20 mi along the highway. When the car reached the location of the second officer 19 min​ later, it was clocked going 60​ mi/hr. The driver of the car was given a ticket for exceeding the 60​ mi/hr speed limit. Why can the officer conclude that the driver exceeded the speed​ limit?

Answer 1

Answer:

We know from the basic speed distance relation that

$Speed=\frac{Distance}{Time}$

Since the car started from rest and it covered the distance between the 2 officer's in 19 minutes we have speed of the car

$Speed=\frac{Distance}{Time}\\\\Speed=\frac{20}{\frac{19}{60}}=63.16mph$

Which clearly exceeds the limit of $60\frac{mi}{hr}$