JEE Mains · Physics · STD 11 - Motion in straight line
- JEE Mains 2022
- Medium
- MCQ
The velocity of the bullet becomes one third after it penetrates \(4\,cm\) in a wooden block. Assuming that bullet is facing a constant resistance during its motion in the block. The bullet stops completely after travelling at \((4+x)\,cm\) inside the block. The value of \(x\) is\(.....\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(0.5\)
Step-by-step Solution
Detailed explanation
\(\left(\frac{ V }{3}\right)^{2} = V ^{2}-2 a (4) \Rightarrow a =\frac{8 V ^{2}}{9(8)}=\frac{ V ^{2}}{9}\)
\(0= V ^{2}-2 a (4+ x )\)
\(V ^{2} =2\left(\frac{ V ^{2}}{9}\right)(4+ x )\)
\(4.5 =4+ x\)
\(x =0.5\)
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