Physics · PYQ NEET UG 2019(2)
हिन्दीTwo bullets are fired horizontally and simultaneously towards each other from roof tops of two buildings \( 100\text{ m} \) apart and of same height of \( 200\text{ m} \), with the same velocity of \( 25\text{ m/s} \). When and where will the two bullets collide? (\( g = 10\text{ m/s}^2 \))
Correct answer · Option 2
After \( 2\text{ s} \) at a height of \( 180\text{ m} \)
Explanation
Time to cover distance \( d = 100\text{ m} \) with relative velocity \( v_{rel} = 25 + 25 = 50\text{ m/s} \) is \( t = \frac{100}{50} = 2\text{ s} \). Height fallen in time \( 2\text{ s} \) is \( h' = \frac{1}{2}gt^2 = \frac{1}{2}(10)(2)^2 = 20\text{ m} \). Height from ground = \( 200 - 20 = 180\text{ m} \).