COMEDK · Physics · 3. Motion In One Dimension
A ball is dropped from the top of the building \(100 \mathrm{~m}\) high. Simultaneously, another ball is thrown upwards from the bottom of the building with such a velocity that the balls collide exactly mid-way. What is the speed in \(\mathrm{ms}^{-1}\) with which the second ball is thrown? (Take, \(g=10 \mathrm{~ms}^{-2}\) )
- A \(31.6\)
- B \(27.8\)
- C \(22.4\)
- D \(19.6\)
Answer & Solution
Correct Answer
(A) \(31.6\)
Step-by-step Solution
Detailed explanation
The given situation is shown in the figure. For the first ball, time taken to reach at mid point \(A\), \[ \begin{aligned} t &=\sqrt{\frac{2 h}{g}} \\ &=\sqrt{\frac{2 \times 50}{10}}=\sqrt{10} \mathrm{~s} \end{aligned} \] For the second ball,…
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