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प्रश्न
A camera is accidentally knocked off an edge of a cliff 400 ft high. The camera falls a distance of s = 16t2 in t seconds. How long does the camera fall before it hits the ground?
उत्तर
The camera falls a distance of s = 16t2 in t seconds
s = 400 ft
∴ 16t2 = 400
t2 = `400/16` = 25
t = 5 sec
∴ Camera falls for 5 sec before it hits the ground.
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