Answer
a) 3.1 $\times$ $10^{3}$ J
b) 2.2 $\times$ $10^{2}$ J
Work Step by Step
a) Work done = $\Delta$$E_{k}$
= 0.5m$v^{2}$ - 0.5m$u^{2}$
= 0.5(7.3)($29^{2}$) - 0
$\approx$ 3.1 $\times$ $10^{3}$ J
b) Work done = $\Delta$$E_{k}$
= 0.5m$v^{2}$ - 0.5m$u^{2}$
= 0.5(0.0026)($410^{2}$) - 0
$\approx$ 2.2 $\times$ $10^{2}$ J
