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 :
Solution
<p>S = 4 cm</p>
<p>$v{'_4} = {v \over 3}$, a = constant</p>
<p>${v_{4 + x}} = 0$</p>
<p>$\left( {{v^2} - {{{v^2}} \over a}} \right) = 2a(4)$</p>
<p>$({v^2} - 0) = 2a(4 + x)$</p>
<p>${4 \over {4 + x}} = {8 \over 9}$</p>
<p>$\Rightarrow x = 0.5$ m</p>
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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