Identify the initial conditions y(0) and y'(0) for the vertical motion of an object , if the object thrown downward at a velocity of 6 feet per second from a height of 30 feet. [Take the origin to be on the ground.]
A) y(0) = 30, y'(0) = -6
B) y(0) = 0, y'(0) = -6
C) y(0) = 30, y'(0) = 6
D) y(0) = 0, y'(0) = 6

Question

Quizplus · Accepted Answer

Since the object is thrown downward at a velocity of 6 feet per second from a height of 30 feet, it means that at time t=0 seconds, the object is at a height of 30 feet above the ground and is moving downward with a velocity of 6 feet per second. Therefore, the initial position is y(0)=30 feet and the initial velocity is y'(0)=-6 feet per second. Hence, the correct choice is A.

Identify the Initial Conditions Y(0) and Y'(0) for the Vertical