Question

Two police patrol cars with radars are 5 miles apart on a highway. As a car passes the first patrol car, its speed is clocked at 55 miles per hour. Four minutes later, when the car passes the second patrol car, its speed is clocked at 50 miles per hour. Prove that the truck must have exceeded the speed limit (of 55 miles per hour) at some time during the 4 minutes.

Answer 1

Answer:

hope it will help you

Step-by-step explanation:

the ans is 75 mph

Answer 2

Hence, Prove that the truck traveling speed is  $75 \frac{miles}{hr}$ during 4 minutes is more than the speed limit of $55 \frac{miles}{hr}$.

Step-by-step explanation:

Time passes first patrol car $=0$

Time passes second patrol car $=4 minutes=\frac{1}{15}$

Let s(t) function represents the distance traveled by truck

$s(0)=0$

$s(\frac{1}{5} )=5$

average velocity ,

$\[ & =\frac{5-0}{\frac{1}{15}-0} \\ \\ & =\frac{5}{15}=75\frac{miles}{hr} \\ \\\end{align}\]$

Assume s(t) differentiable.

The time, t where truck traveling with speed of $75 \frac{miles}{hr}$  during 4 minutes.

Hence proved that the truck speed is more than the speed limit $55 \frac{miles}{hr}$ .