Work Energy And Power Question 287
Question: An object of mass 2.0 kg makes an elastic collision with another object of mass M at rest and continues to move in the original direction but with one-fourth of its original speed. What is the value of M?
Options:
A) 0.75kg
B) 1.0kg
C) 1.2kg
D) None of these
Show Answer
Answer:
Correct Answer: D
Solution:
[d] For the object of mass 2.0 kg.
$ \frac{\Delta k}{k}=\frac{k-k/4}{k}=\frac{3}{4} $
Kinetic energy transferred $ \frac{\Delta k}{k}=\frac{4m_1m_2}{{{( {m_1}+m_2 )}^{2}}} $
Here, $ {m_1} = 2.0 kg, m_2= M $
$ \therefore \frac{3}{4}=\frac{4\times 2M}{{{( 2+M )}^{2}}}\Rightarrow M=\frac{2}{3}kgor6kg $
