The starter in your car is a device of fixed resistance that is designed to operate at a power of 847 W when connected to a fresh 12.0 V car battery, but is able to function at a power as low as 612 W when the battery is weaker. Your car battery is several years old, and one morning you are unable to start the vehicle. You check the battery's voltage, and find a value of 10.6 V when the ignition is in the off position. You have a friend try to start the vehicle, and as the engine turns over, the voltage of the battery drops to 7.83 V. What is the internal resistance of the battery?

The starter in your car is a device of fixed resistance that is designed to operate at a power of 847 W when connected to a fresh 12.0 V car battery, but is able to function at a power as low as 612 W when the battery is weaker. Your car battery is several years old, and one morning you are unable to start the vehicle. You check the battery's voltage, and find a value of 10.6 V when the ignition is in the off position. You have a friend try to start the vehicle, and as the engine turns over, the voltage of the battery drops to 7.83 V. What is the internal resistance of the battery?