math
posted by erin on .
One of the world's fastest roller coasters is located in a theme park in Valencia, California. Riders go from 0 to 100 miles per hour in 7 seconds. Find the acceleration of the roller coaster during this time interval in miles per second squared.
Math  Reiny, Monday, March 8, 2010 at 9:46am
acceleration = change in velocity/change in time
= 100 miles per hour/7 second
= (100 miles per 3600 seconds)/7 seconds
= 100 miles/25200 sec^2
= .004 miles/sec^2 (correct to 3 decimals
why was the numerator and denominator multiplied by 3600

the original velocity was in miles/hour
but the question asked for miles/second
how many seconds are there in an hour?