A vertically projected particle passes a point P at times t and 3t. If H is the maximum height above the point of projection and h is the height of P above the point of projection, then H/h is:
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A vertically projected particle passes a point P at times t and 3t. If H is the maximum height above the point of projection and h is the height of P above the point of projection, then H/h is:

G1 Physics · Accepted Answer

At height P: ut − gt²/2 = 3ut − 9gt²/2. Therefore 2ut = 4gt² ⇒ u = 2gt. Maximum height: H = u²/(2g) = 2gt². Height of P: h = ut − gt²/2 = 2gt² − gt²/2 = 3gt²/2. Hence H/h = 2/(3/2) = 4/3.