JEE Mains · Physics · STD 11 - Work,energy,power and collision
- JEE Mains 2021
- Medium
- MCQ
An object of mass \(m _{1}\) collides with another object of mass \(m _{2}\), which is at rest. After the collision the objects move with equal speeds in opposite direction. The ratio of the masses \(m _{2}: m _{1}\) is
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(3:1\)
Step-by-step Solution
Detailed explanation
\(m _{1} v _{1}=- m _{1} v + m _{2} v\)
\(v _{1}=- v +\frac{ m _{2}}{ m _{1}} v\)
\(\frac{\left( v _{1}+ v \right)}{ v }=\frac{ m _{2}}{ m _{1}}\)
\(e =\frac{2 v }{ v _{1}}=1\)
\(v =\frac{ v _{1}}{2}\)
\(\frac{ v _{1}+ v _{1} / 2}{ v _{1} / 2}=\frac{ m _{2}}{ m _{1}}\)
\(3=\frac{ m _{2}}{ m _{1}}\)
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