while getting ready to leave a football game, a spectator dropped a seat cushion

Question

while getting ready to leave a football game, a spectator dropped a seat cushion off the back of the stadium 35m above the ground. while watching the cushion fall to the ground, his sunglasses slipped off his face and also fell to the ground. if the glasses hit the ground 1.5 seconds after the cushion, what was the velocity of the cushion at the time the glasses started to fall to the ground and how far above the ground were the glasses when the cushion hit the ground?

Please help, I got this wrong and need to know what I did wrong for a test.

Explanation / Answer

Here ,

height , h = 35 m

as the time of flight is same for both cushion and sun glasses

t = 1.5 s

Using first equation of motion

v= 1.5 * 9.8

v = 14.7 m/s

the speed of cushion at the time is 14.7 m/s

time taken to fall ,

t = sqr(2 * 35/9.8)

t = 2.67 s

the time elapsed for the suglasses in air

ts = 2.67 - 1.5 = 1.17 s

height = 35 - 0.5 * 9.8 * 1.17^2

height = 28.3 m

glasses is 28.3 m above ground

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