a car travels 400.0 miles in a total of 8.0 hrs. what is the average speed of this car during the trip showing work

Answer 1

Hi Adis H.,

You could start by asking yourself, in what units should I expect average speed (total distance/total time) of a car to be measured? If you said, miles/hr, you're on the right track. So how can you perform a simple math operation on the initial given conditions: 400.0 miles and 8.0 hours, in order to get a quotient with those units? (Do it). Then, you need to consider, what is the #SignificantDigits of each of the input data, so what is the #SignificantDigits you should express your result as?

But now, time for some fun! Your instructor's request was, "showing work". Work (in physical science), as you may already know, is energy expended in providing a force (to counter rolling friction, at least) over a distance. So go wild, look up rolling friction data for cars, also look up wind resistance values (you may need to calculate to get for that average speed, since wind resistance is NOT linear with speed), total those as forces, and multiply by the distance. That will be the work done by the car engine. "You said, 'showing work' ...."

-- Cheers, --Mr. d.