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A stone is dropped from the top of the top of cliff reaches it foot in 4 s. calculate the height of the cliff and the velocity with which stone reaches the ground.(g=10m\s^2) |
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Answer» h = 80 m, v = 40 m/sExplanation:Givena stone is dropped from the top of the cliffTime taken for stone to reach the ground = 4sLet height be 'h' and final velocity be 'v'a = G = 10m/s²As it is a freely falling body initial velocity is zero i.e., U = 0.We know thats = ut + 1/2 at²⇒h = ut + 1/2 at² [ here DISPLACEMENT of stone is height of the cliff]⇒h = 0 + 1/2 10*(4)²∴ h = 5*16 = 80 m∴ h = 80 mWe know thatv = u + at⇒v = 0 + 10*4∴v = 40 m/s |
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