Mangastream said:Then why do you say that 9V x 0.12Ah = 1.08 Joules is way too small?
The formula for calculating electrical energy stored in a battery is E = V x Q, where E is energy (in watt-hours), V is voltage (in volts), and Q is capacity (in ampere-hours). In this case, we would calculate it as follows: E = 9V x 0.12 Ah = 1.08 watt-hours.
The unit mAh stands for milliampere-hour, which is a smaller unit of measurement than Ah (ampere-hour). Since batteries typically have a low capacity, it is more convenient to use mAh to represent the small amount of current a battery can provide.
The energy stored in a battery is not constant and will decrease over time as the battery is used. This is due to internal resistance and chemical reactions within the battery. The rate of energy decrease will depend on the type and quality of the battery.
Yes, the formula E = V x Q can be used to calculate the energy stored in any type of battery. However, it is important to note that the voltage and capacity values may differ for different types of batteries and should be adjusted accordingly.
The length of time a battery will last before needing to be replaced depends on the voltage and current draw of the device it is being used in. To calculate the approximate runtime, simply divide the battery's capacity (in mAh) by the current draw (in mA) of the device. For example, if a device draws 10 mA, the battery would last approximately 12 hours (120 mAh / 10 mA = 12 hours).