InterviewSolution
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InterviewSolution
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Show that there are two values of time for which a projectile is at the same height. Also show mathematically that the sum of these two times is equal to the time of flight. |
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Answer» Correct Answer - A For vertically upward motion of a projectile, `y=(u sin alpha)t - 1/2 (g t^2) or 1/2 g t^2 -(usin alpha)t+y=0` This is a quadratic equation in t. Its roots are `t_(1)=(u sing alpha-sqrt(u^(2)sin^(2)alpha-2gy))/(g)` and `t_(2)=(us sin alpha+sqrt(u^(2)sin^(2)alpha-2gy))/(g)` `:. t_(1)+t_(2)=(2u sin alpha)/(g)=T` (time of flight of the projectile). |
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