Question

A golfer takes a swing from a hill twenty feet above the cup with an initial upwards velocity of 76 feet per second. How long does it take the ball to land on the ground near the cup?

Answer 1

t = 5 seconds

Explanation:

A golfer takes a swing from a hill twenty feet above the cup with an initial upwards velocity of 76 feet per second.

We need to find how long does it take the ball to land on the ground near the cup.

The equation for the path of the ball is given using second equation of kinematics as follows :

`-16t^2+76 t+20=0\\\\\text{or}\\\\-4t^2+19t+5=0\\\\-4t^2+20t-t+5=\\\\-4t(t-5)-1(t-5)=0\\\\(t-5)(-4t-1)=0\\\\t=5, t=(-1)/(4)\ s`

Neglecting negative value,

It will take 5 seconds for the ball to land on the ground near the cup.