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Chapter 27: Q. 38 (page 763)

An ideal battery would produce an extraordinarily large current if "shorted" by connecting the positive and negative terminals with a short wire of very low resistance. Real batteries do not. The current of a real battery is limited by the fact that the battery itself has resistance. What is the resistance of a 9.0V battery that produces a 21A current when shorted by a wire of negligible resistance?

Short Answer

Expert verified

The resistance of a9.0Vbattery that produces a21Acurrent when shorted by a wire of negligible resistance is429mΩ.

Step by step solution

01

Given Information

Voltage=9.0V

Current=21A

02

Explanation

By applying Ohm's law, we can find the resistance,

r=UI→(1)

Assuming ris the battery's internal resistance (which is always denoted by rwhen compared with external resistances).

Substitute the values in equation (1)

r=9V21A

=0.429Ω

03

Final Answer

Hence, the resistance is429mΩ.

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Most popular questions from this chapter

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