You can determine the speed of a car by measuring the time it takes to travel between mile markers on a?

Question

highway. a) How many seconds should elapse between two consecutive mile markers if the car's avg. speed is 65 mi/h? b) What is the car's avg. speed if it takes 65 seconds to travel between the mile markers? I'd appreciate any help, thank you

Answer 1

1 minute has 60 seconds and so in the first case,

a) it should take less than a minute. 60/65 minutes and multiplying by 60 we get 55.4 seconds

b) the average speed is <60 mph since 1 mile takes 65 seconds and so in 60 seconds, the car would go 60/65 multiplied by 60 miles per hour. 60 x 60 / 65 = 720/13 = 55.4 mph approx.

Note that in both cases, we get the same numerical answer but the units and the significance are different.

Answer 2

Since a car traveling 60 mph is traveling a mile a minute, the speed in MPH is SpeedMPH=60/timeSeconds x 60 simplified, SpeedMPH = 3600/ timeSeconds

Answer 3

a) distance =1 mile, avg. speeed =65 mi/h
as time= distance / speed, we get time= 1/65 hours

b) time= 65 sec
speed= distance/time= 1/65 mi/sec

Answer 4

the formula for instant velocity is v= d/t
velocity equals distance divided time,
a) First convert velocity from m/h to m/s: 65mi/h * (1h/3600s) =0.018 mi/s. Regroup the formula to t = d/v, so t = 2mi/0.018
t = 111 seconds to carry 2 miles going 65 mi/h.
b) v = d/t, so if its two miles, v = 2mi/65 sec
v = 0.031 mi/s, converted into mi/h 0.031 mi/s * (3600s) = 110 miles per hour

Answer 5

2miles / 65 mph is the time it would take to go 2 miles
about 110.8 seconds

65 seconds is equal to .0181hours

so 2m/.0181hrs = 110.5 miles per hour