Question

A water balloon dropped from a window high above the ground falls y = 4.9t2 m in t sec. find the balloon’s (a) average speed during the first 3 sec of fall. (b) speed at the instant t = 3.

Answer 1

For the average speed, I multiplied 4.9 by 3 squared to receive 44.1, then divided that by 3 to receive 14.7 m/s. 4.9 X 4.9 X 4.9 = 44.1(Distance traveled / fall time)44.1 ÷ 3 = 14.7 m/s

For the speed at t = 3, I took the derivative of 4.9t2 to make it 2(4.9)t and then plugged in 3 to receive an answer of 29.4 m/s. derivative   =2(4.9)t                    =2(4.9)3                    =29.4 m/s