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Physics · PYQ NEET UG 2023
हिन्दीA horizontal bridge is built across a river. A student standing on the bridge throws a small ball vertically upwards with a velocity \( 4\text{ m s}^{-1} \). The ball strikes the water surface after \( 4\text{ s} \). The height of bridge above water surface is (Take \( g = 10\text{ m s}^{-2} \)) :
Correct answer · Option 1
\( 64\text{ m} \)
Explanation
Using equation of motion: \( h = -ut + \frac{1}{2}gt^2 \). Here \( u = -4\text{ m s}^{-1} \), \( t = 4\text{ s} \), \( g = 10\text{ m s}^{-2} \). Thus, \( h = -4(4) + \frac{1}{2}(10)(4)^2 = -16 + 80 = 64\text{ m} \).
