JEE Mains · Physics · STD 11 - Work,energy,power and collision
- JEE Mains 2020
- Medium
- Numerical
A block of mass \(1.9\, kg\) is at rest at the edge of a table, of height \(1\, m\). A bullet of mass \(0.1\, kg\) collides with the block and sticks to it. If the velocity of the bullet is \(20\, m / s\) in the horizontal direction just before the collision then the kinetic energy just before the combined system strikes the floor, is \(....J\) [Take \(g =10\, m / s ^{2}\). Assume there is no rotational motion and loss of energy after the collision is negligable. \(]\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) \(21\)
Step-by-step Solution
Detailed explanation
\(p _{ i }= p _{ f } \Rightarrow 0.1 \times 20=2 v\)
\(\therefore v =1 m / s\)
\(KF _{ f }= mgh +\frac{1}{2} mv ^{2}=20+1=21\)
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