A 0.5 kg block moving at a speed of 12 ms$-$1 compresses a spring through a distance 30 cm when its speed is halved. The spring constant of the spring will be _______________ Nm$-$1.
Answer (integer)
600
Solution
<p>$${1 \over 2}m\,{V^2} = {1 \over 2}k{x^2} + {1 \over 2}m{\left( {{v \over 2}} \right)^2}$$</p>
<p>$\Rightarrow {3 \over 8}m{v^2} = {1 \over 2}k{x^2}$</p>
<p>$\Rightarrow k = {3 \over 4} \times {1 \over 2} \times {{144} \over 9} \times 100$</p>
<p>$= 600$</p>
<p>$\Rightarrow 600$</p>
About this question
Subject: Physics · Chapter: Work, Energy and Power · Topic: Work Done by a Force
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