JEE Mains · Physics · STD 11 - 2. motion in straight line
An engine of a train, moving with uniform acceleration, passes the signal-post with velocity \(u\) and the last compartment with velocity \(v\). The velocity with which middle point of the train passes the signal post is
- A \(\sqrt{\frac{ v ^{2}+ u ^{2}}{2}}\)
- B \(\frac{ v - u }{2}\)
- C \(\frac{ u + v }{2}\)
- D \(\sqrt{\frac{ v ^{2}- u ^{2}}{2}}\)
Answer & Solution
Correct Answer
(A) \(\sqrt{\frac{ v ^{2}+ u ^{2}}{2}}\)
Step-by-step Solution
Detailed explanation
\(\left( v ^{\prime}\right)^{2}= u ^{2}+2 ad\) \(v ^{2}=\left( v ^{\prime}\right)^{2}+2 ad\) solving, we get \(v^{\prime}=\sqrt{\frac{v^{2}+u^{2}}{2}}\)
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