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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.

Respuesta :

Answer:

86.4 m  horizontal from landing spot

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

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