A projectile is launched upward from an initial height of 400 feet, and it lands on the ground after 8 seconds. What was the initial velocity of the projectile?
A) 78 feet/second
B) 88 feet/second
C) 68 feet/second
D) 70 feet/second

Question

Quizplus · Accepted Answer

The correct answer is A because the initial velocity of the projectile is 78 feet/second. This can be calculated using the formula v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration due to gravity (-32 feet/second^2), and t is the time. In this case, the final velocity is 0 feet/second, the time is 8 seconds, and the acceleration due to gravity is -32 feet/second^2. Substituting these values into the formula, we get 0 = u + (-32) * 8, which simplifies to u = 78 feet/second.

A Projectile Is Launched Upward from an Initial Height of 400