Now determine the precise time that the cars started their trip (hour:minute:second) if Car 1 passed the streetlight at 12:25:00 and was 25 seconds before Car 2. Hint: Determine how far the cars traveled and then use the known velocity of Car 1 to estimate how much travel time it needed to go that distance.

This question is incomplete, the missing part is in the image below;

the precise time that the cars started their trip is 12:00:00

Explanation:

Given that;

from the image; The velocity of car1 V1 = 1/60 mile/seconds

Given the precise time that the car 1 passed the streetlight ( 12:25:00 )

if car 1 passed 25 seconds before car 2

meaning Car 2 passed the the streetlight at 12:50:00

now time delay is the difference between the two times; i.e

12:50:00 - 12:25:00 = 25 sec

so the distance between starting point and streetlight = 25×1 = 25 miles

Now, time required for Car1 to travel 25 miles distance will be;

t = distance/velocity of car1 = 25 / ( ) = 1500 sec = 25 min

so the precise time that the cars started their trip will be;

12:25:00 - 25 min = 12:00:00

Therefore, the precise time that the cars started their trip is 12:00:00

electric field is a function of 1/r^2

yes, the force per unit charge for a point charge is inverse square law.