Problema Solution

A tennis player hits a ball 3 feet above the ground with a velocity of 45 ft/sec. When will the ball be at a height of 3 feet again (Round to 3 decimal places)?

Answer provided by our tutors

The equation used to model the height of an object after t seconds is given by the function:

h(t)=-16t^2 + V0t + S0, where v0 is the initial velocity applied on an object and S0 is the initial height

In our case S0 = 3 ft, V0 = 45 ft/sec and we need to solve the equation h(t) = 3 that is:

-16t^2 + 45t + 3 = 3

........

click here to see the equation solved for t

........

t = 2.813 sec

We need to ignore the solution t = 0 since that is the moment when the object is hit, so we need the nonnegative solution.

It takes 2.813 seconds for the ball to be at a height of 3 feet again.