Practice portal › Motion in a Straight Line › Two Bodies under Gravity and Successive Drops
Asked in JEE Main 5th Sept 1st Shift 2020 · Successive drops
Helicopter from rest with acceleration g: at height h its speed is v = √2gh, upward.
The packet leaves with this upward velocity and then falls freely. Upward positive: -h = √2gh t - 1/2gt².
1/2gt² - √2gh t - h = 0 ⇒ t = (√2gh + √2gh + 2gh)/g = (√2gh + 2√gh)/g.
t = (√2 + 2)√/hg = 3.4√/hg.
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