The angular speed of an automobile engine is increased at a constant rate from 1200rev/min to 3000rev/min in 12s. How many revolutions does the engine make in this 12s interval?

I worked it out to be 25200 rev. Is that right?

3 answers

average speed times time: 2100rev/min multiplied by 12/60 min? No way your answer is correct. What is important here is you need to examine how you got that (I know what you did...you did not use units to check to see what came out is in the right units, ie, time divided out).
Oh, I had to find it in rev/min^2.
Er, wait. That is probably wrong. I think I have to go back and convert a few things around.