The discussion compares the energy output of a bullet to that of an AA battery, focusing on kinetic energy and battery capacity. The kinetic energy of a bullet is calculated using the formula 1/2mv², while the energy of a battery is measured in watt-hours, with a conversion factor of 2.78 x 10-4 to convert joules to watt-hours. A standard AA battery's capacity is defined as the product of 20 hours multiplied by the constant current it can supply, typically rated at 100 A·h for a 20-hour discharge at room temperature. The discussion also highlights the difference between disposable and rechargeable batteries in terms of lifecycle and energy delivery.
PREREQUISITESEngineers, physicists, and anyone interested in comparing energy outputs of projectiles and batteries, particularly in applications related to energy efficiency and performance analysis.
http://en.wikipedia.org/wiki/Battery_power#Battery_capacity_and_dischargingThe capacity printed on a battery is usually the product of 20 hours multiplied by the constant current that a new battery can supply for 20 hours at 68 F° (20 C°), down to a specified terminal voltage per cell. A battery rated at 100 A·h will deliver 5 A over a 20-hour period at room temperature.