JEE Mains · Physics · STD 11 - 2. motion in straight line
A stone is dropped from the top of a building. When it crosses a point \(5\, m\) below the top, another stone starts to fall from a point \(25\, m\) below the top. Both stones reach the bottom of building simultaneously. The height of the building is ..... \(m\).
- A \(35\)
- B \(45\)
- C \(50\)
- D \(25\)
Answer & Solution
Correct Answer
(B) \(45\)
Step-by-step Solution
Detailed explanation
displacement of the first stone when second is dropped \(=5 m\), time difference in dropping of the stones is \(t =\frac{2 h }{ g }=1\; s\) \(h =\frac{1}{2} g t ^{2}=\frac{1}{2} g ( t -1)^{2}+25 \Rightarrow t =3 \;s\) thus,…
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