Question

A toy rocket is launched straight up into the air, at the edge of a bridge, 28 m from the ground. If the launch velocity is 35.5 m/s. Gravity is -9.81m/s^2

a. What is the hang time of the rocket?
b. What is the speed of the rocket just before it hits the ground?​

A) 2.32 seconds and 35.5 m/s
B) 5.05 seconds and 17.75 m/s
C) 2.87 seconds and 28 m/s
D) 4.64 seconds and 0 m/s

Answer 1

The hang time of the rocket is 2.32 seconds. The speed of the rocket just before it hits the ground is 22.69 m/s.

Step-by-step explanation:

In order to find the hang time of the rocket, we need to determine how long it takes for the rocket to reach the ground. We can use the formula h = 1/2gt^2, where h is the height, g is the acceleration due to gravity, and t is the time. Plugging in the given values, we have 28 = 1/2(-9.81)t^2. Solving for t, we find t = 2.32 seconds. Therefore, the hang time of the rocket is 2.32 seconds.

To find the speed of the rocket just before it hits the ground, we can use the formula v = gt, where v is the velocity and g is the acceleration due to gravity. Plugging in the given values, we have v = -9.81 * 2.32 = -22.69 m/s. However, since the rocket is launched straight up, the velocity should be positive. Therefore, the speed of the rocket just before it hits the ground is 22.69 m/s.