When the battery is charged then Watt hour =VIt=15×10×8=1200 W/hr. During discharge the watt hour u= 1050 W/hr. ∴ Efficiency of battery =12001050×100=87.5%
A battery is charged at a potential of 15 V for 8 hours when the current flowing is 10 A. The battery on discharge supplies a current of 5 A for 15 hours. The mean terminal voltage during discharge is 14 V. The "Watt-hour" efficiency of the battery is:
Held on 30 Apr 2004 · Verified 9 Jul 2026.
82.5%
80%
90%
87.5%
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