Question

A paratrooper jumps from a plane at an altitude of 4500 ft and descends at the rate of 20 ft/sec. What is the formula for the paratrooper’s height, h, above the ground after t seconds?

A:h=4500/20t
B:h=20t+4500
C:h=4500+20t
D:h=4500/20*t

Answer 1

Lets test if a paratrooper is descending at a rate of 20 feet per second and he has been in the air for 10 seconds how far away is he from the ground.  20 x 10 = 200 feet.  Now we subtract 200 from 4500 to get 4300.  Which means the equation has to be h = 4500-20 · T and it looks like your answer might be D.  Hope this helped.

Answer 2

Answer:

The correct answer is option B

Step-by-step explanation:

Let the change in height after "t" seconds be "h"

Thus, the mathematical equation can be written as

$t = \frac{d}{v} \\t = \frac{4500 -h}{-20}\\-20 t = 4500 -h\\h = 4500 + 20t$

Thus, the correct answer is option B