The battery of a mobile phone is rated as $4.2 \mathrm{~V}, 5800 \mathrm{mAh}$. How much energy is s

Question

The battery of a mobile phone is rated as $4.2 \mathrm{~V}, 5800 \mathrm{mAh}$. How much energy is stored in it when fully charged?\

Professor PC Thomas Classes · Answer

(a): $V=4.2 \mathrm{~V}, q=5800 \mathrm{mAh}$ Energy = $q V=5800 	imes 10^{-3} 	imes 60 	imes 60 	imes 4.2$\ $=87.7 	imes 10^{3} \mathrm{~J}=87.7 \mathrm{~kJ}$\