How does the clock in a handphone continue working even when it's switched off?

Question

when you switch off a phone and switch it on again, the time is correct. why doesnt it show the time from when i switched the phone off?

Answer 1

well the battery i still attached to the phone, so even if the phone's off, there's a small reserve to keep the clock running. nevertheless if your battery dies and the phone stays off long enough, the time and date will be erased from the phone and you might have to set it again.