Question

At a particular instant, a hot air balloon is 100 m in the air and descending at a constant speed of 2.0 m/s. at this exact instant, a girl throws a ball horizontally, relative to herself, with an initial speed of 20 m/s. when she lands, where will she find the ball? ignore air resistance.

Answer 1

86.4 m horizontal from landing spot

Step-by-step explanation:

Find out how long before the ball hits the ground

vertical speed of ball = -2 m/s gravity = - 9.81 m/s^2

find time to hit ground from 100 m

( height will be zero when it hits the ground)

0 = 100 - 2 t - 1/2 ( 9.81) t^2

use Quadratic Formula to find t = 4.32 seconds

horizontal speed of ball = 20 m/s

in 4.32 seconds it will travel horizontally 20 m/s * 4.32 s = 86.4 m