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प्रश्न
A stone is dropped from a cliff 98 m high.
What will be its speed when it strikes the ground?
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उत्तर
Height of cliff = 98 m.
Initial velocity of stone = 0 ms-1.
Acceleration due to gravity = 9.8 ms-2.
Final velocity when it strikes the ground
V2 - u2 = 2 g H
V2 = 2X9.8X98
V2= 1920
V= 44.6 ms-1.
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