Question

After an​ accident, police can estimate the speed that a car was traveling by measuring its skid marks. The formula v equals 2 StartRoot 5 Upper L EndRoot can be used where v is the​ speed, in miles per​ hour, and L is the length of the skid​ marks, in feet. ​(a) Estimate the speed of a car that left skid marks 60 ft long. ​(b) If the posted speed limit is 50 mph should the police officer believe the​ driver's claim that he was not​ speeding?

Answer 1

Answer:

a) 34.64 mph

b) The police officer should believe the claim that the driver was not speeding.

Explanation:

v = 2√(5L)

where,

v is the​ speed, in miles per​ hour

L is the length of the skid​ marks in feet

a) When L = 60 ft

$v=2\sqrt{5L}\\\Rightarrow v=2\sqrt{5\times 60}=34.61\\\Rightarrow v=34.64\ mph$

b) The speed of the car was 34.64 mph which is under the speed limit of 50 mph. So, the police officer should believe the claim that the driver was not speeding.