Question 264: Work, Energy and Power & Circular Motion

Question

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.

Accepted Answer

$${1 \over 2}m\,{V^2} = {1 \over 2}k{x^2} + {1 \over 2}m{\left( {{v \over 2}} ight)^2}$$
$$ \Rightarrow {3 \over 8}m{v^2} = {1 \over 2}k{x^2}$$
$$ \Rightarrow k = {3 \over 4} 	imes {1 \over 2} 	imes {{144} \over 9} 	imes 100$$
$$ = 600$$
$$ \Rightarrow 600$$

Work, Energy and Power & Circular Motion

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.

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