A car is moving with speed of $150 \mathrm{~km} / \mathrm{h}$ and after applying the break it will move $27 \mathrm{~m}$ before it stops. If the same car is moving with a speed of one third the reported speed then it will stop after travelling ___________ m distance.
Answer (integer)
3
Solution
<p>${F_R}\,d = {1 \over 2}m{v^2}$</p>
<p>$${{{d_2}} \over {{d_1}}} = {\left( {{{{v_2}} \over {{v_1}}}} \right)^2} = {\left( {{1 \over 3}} \right)^2}$$</p>
<p>${d_2} = {d_1} \times {1 \over 9} = 3m$</p>
About this question
Subject: Physics · Chapter: Kinematics · Topic: Motion in a Straight Line
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