A stuntman jumps from a rooftop 315 ft off the ground. how long will it take him, falling freely, to reach the ground? (use the formula s = 16t2.)

For this case what you must do is replace the value of the height in the given equation and clear the value of t.

We then have to replace:

s = 16 * t ^ 2

315 = 16 * t ^ 2

Clearing the value of t:

315 = 16 * t ^ 2

t1 = root (315/16)

t1 = 4.437059837

t2 = - root (315/16)

t2 = - 4.437059837

We ignore the negative root.

Answer:

it will take him, falling freely 4.43 s to reach the ground