A spring of force constant is slowly compressed by a distance

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A spring of force constant

k

is slowly compressed by a distance

x

. Which option correctly states the work done (i) by the external agent on the spring and (ii) by the spring force during this process? (a) (i)

-\dfrac{1}{2}kx^{2},\; (ii)\; +\dfrac{1}{2}kx^{2}

(b) (i)

+kx^{2},\; (ii)\; -kx^{2}

+\dfrac{1}{2}kx^{2},\; (ii)\; -\dfrac{1}{2}kx^{2}

(d) (i)

+\dfrac{1}{2}kx^{2},\; (ii)\; +\dfrac{1}{2}kx^{2}