JEE Mains · Physics · STD 11 - 2. motion in straight line
A passenger train of length \(60\, m\) travels at a speed of \(80\, km/hr\). Another freight train of length \(120\, m\) travels at a speed of \(30\, km/hr\). The ratio of times taken by the passenger train to completely cross the freight train when: \((i)\) they are moving in the same direction, and \((ii)\) in the opposite directions is
- A \(2.2\)
- B \(2.5\)
- C \(1.5\)
- D \(\frac{25}{11}\)
Answer & Solution
Correct Answer
(A) \(2.2\)
Step-by-step Solution
Detailed explanation
\begin{array}{l} Time\,taken\,if\,both\,moving\,in\,same\,direcation\\ \,\,\,\,\,\,\,\,\,\,\,\,{t_1} = \frac{{{\rm{distance}}}}{{speed}} = \frac{{0.12 + 0.06}}{{80 - 30}} = \frac{{0.18}}{{50}}\\ Time\,taken\,if\,moving\,in\,opposite\,direction\\ \,\,\,\,\,\,\,\,\,\,\,{t_2} =…
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