usually a 3 pin connector is used for a fan that can be controlled. The 3 pins are active ground and sense (the reporting of fan speed)
hard drive.
the computer component not tested by post rutine is the power supply
The computer component that presents the most risk of electric shock is the power supply. Since there are large capacitors in the power supply, it is possible that you might get shocked, even with the power supply unplugged.Another component that presents a shock risk is an internal modem. You might grab a hold of it while there is an incoming phone call, and then get shocked from the ringer current.
In the case of a desktop computer a power supply that in turn plugs into a household outlet provides power to the internal components of the computer. In the case of a laptop or tablet a battery provides power.
Usually the power supply.
That is a device that is inside the computer. An internal hard drive, for instance, is physically mounted inside the computer. It is not made to be used outside the computer, though there are kits to convert internal hard drives into external drives. There are external storage devices that are made to plug into a USB port. External devices either require their own power supply, or they get power from a USB socket. Internal devices get their power from the power supply which is already in the computer.
because a computer Component can only Communicate in Power on (1)Power off (0) otherwise it is a quantum computer and there is no sutch thing.
the power supply provides electricity to each component to the computer and ensures that neither too much or too little power is delivered. it is generally box shaped with many wires coming from it which will be used to connect to each component of a computer
A computer's power supply unit provides all needed voltages for the components of a computer that are internal. Externals either draw power from the USB bus (which in turn gets it's power from the aforementioned PSU or a Hub with a power supply) OR have their own internal power supply with a cable.
Good power supply and good cooling.
hard drive
Gasoline is a hydrocarbon obtained by separating crude oil into component fractions in a fractionating column; so yes a hydrocarbon can power an internal combustion engine.