Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. 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:

JEE MainJEE Main 2022Laws of Motion

Solution:

image
$ \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 ) $
$ \Rightarrow V ^2=2\left(\frac{ V ^2}{9}\right)(4+ x )$
$ 4.5=4+ x $
$ x =0.5$