A cell phone charger operates at 5 volts and can deliver a maximum current of 1.0 Amp. If your cell phone has an energy storage capacity of 38.9~38.9 kiloJoules, what is the shortest possible time (in hours) it would take to fully charge your empty phone battery using this charger.

it takes 2.16 hrs to fully charge the phone

Explanation:

V = 5v

I = 1A

E = 38.9 Kj = 38900 j

t = ?

E = IVt

t = E/IV

t = 38900 ÷ (1 × 5)

t = 38900 ÷ 5

t = 7780 seconds

t = 7780/3600( converting time in seconds to hours)

t = 2.16 hrs

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