Suppose an object is thrown upward with an initial velocity of 48 feet per second from a height of 120 feet. The height of the object t seconds after it is thrown is given by

Question

H(t)=-16t² +48t+120

a. Find the average velocity in the first two seconds after the object is thrown.

b. Find the average velocity from 𝑡 = 2 to 𝑡 = 4

Answer 1

h'= -32t+ 48 = velocity at time t

from t = 0 to 2, h' = 48 to -16, average = 48-16)/2 = 32/2 = 16 feet per second

from 2 to 4, h' = (-32(4) - 32(2))/2 = -128 -64)/2 = -64 -32 = - 96 feet per second