While deriving the expression for kinetic energy

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

Problem

While deriving the expression for kinetic energy, the displacement is written as

s=\frac{v^{2}-u^{2}}{2a}

. Substituting this into

W=Fs

and using

F=ma

, which intermediate expression is obtained before any further simplification? (a)

W = m (v^{2}-u^{2})

(b)

W = \dfrac{m (v - u)^{2}}{2}

(c)

W = ma\left(\dfrac{v^{2}-u^{2}}{2a}\right)

(d)

W = \dfrac{1}{2} m (v^{2}-u^{2})