Usb human heater
After seeing the latest in hipsterly-wanky-named products, and suffering from cold hands all the time, i thought - why not build my own.
this is an attempt
In other words, on average the skin absorbs about 80 mW/cm2 to reach 41oC. In addition, skin temperature increases by 0.8oC for each 10 mW/cm2 of absorbed power.
P = VI V = IR
Voltage: 5V Resistance: 65ohm Current: ?
Length = 0.5m Current = 5/32.5 = 0.156A Power = 5 * 0.156 = 0.78W
Voltage: 5V Resistance: 10ohm Current: ?
Length = 1.5m Current = 5/15 = 0.333A Power = 5 * 0.333 = 1.665W