W′=14 W\mathrm{W}^{\prime}=\dfrac{1}{4} \mathrm{~W}W′=41 W
W′=12 W\mathrm{W}^{\prime}=\dfrac{1}{2} \mathrm{~W}W′=21 W
W′= W\mathrm{W}^{\prime}= \mathrm{~W}W′= W
W′=2 W\mathrm{W}^{\prime}=2 \mathrm{~W}W′=2 W