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a ball is projected from ground at an angle 45 degree with horizontal from distance d1 from the foot of a pole and just after touching the top of pole it the falls on ground at the distance d2 from pole on other side the height of pole is |
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Answer» Answer: d1 * d2 / [ d1 + d2 ]. Explanation: We will get the horizontal component to be as X = U cosФ*t = u t/√2 since the value of the Ф is = π/4 and, the distance y = u sinФ t - 1/2 g t^2 will be equal to = u/√2 - 1/2 g t^2
Again we know that the y = x - g x^2 / u^2 since the value of the tanФ = 1 and cosФ =1/√2. If we take x = d1, y = H to be the height of the pole. h = d1 - g d1^2 / u^2 ....(1) Now from the question, when x = d1 + d2 and the value of y = 0. Hence, 0 = (d1+d2) - g (d1 + d2)^2/u^2. u^2 = g (d1 + d2) ...(2) Now if we substitute the EQUATION (2) in (1) we will get: h = d1 - d1^2/(d1+d2) = d1 * d2 / (d1 + d2). So on solving we will get the value as d1 * d2 / [ d1 + d2 ]. |
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