Question

You are piloting a helicopter which is rising vertically at a uniform velocity of 14.7 m/s. When it is 196 m from the ground, a ball is projected from it with a horizontal velocity of 8.5 m/s with respect to the helicopter. Calculate:

a.) When the ball will reach the ground.

A. 10 seconds
B. 12 seconds
C. 14 seconds
D. 16 seconds

Answer 1

The ball will reach the ground in 6.32 seconds.

Step-by-step explanation:

To calculate when the ball will reach the ground, we need to consider the vertical motion of the ball. The initial vertical velocity of the ball is 14.7 m/s and it falls 196 m. We can use the equation for motion in one dimension with constant acceleration to find the time it takes for the ball to reach the ground:

s = ut + (1/2)at^2

Where s is the distance, u is the initial velocity, t is the time, and a is the acceleration.

Plugging in the known values:

-196 = (0) * t + (1/2) * (-9.8) * t^2

Simplifying:

-196 = -4.9t^2

Dividing both sides by -4.9:

t^2 = 40

t = sqrt(40) = 6.32 seconds

Therefore, the correct answer is A) 10 seconds.