It could be incorrect air passage over the engine, from a tired fan belt or from the air from the fan or could be dirt in the brake pads. Best to seek the advice of a qualified mechanic.
It is the alternator....
wheel bearing, gearbox or wind noise Supercharger?
Could be the resonator
Car wheels on the pavement.
The Diff oil ir either needing changed or topped up, if its a whining noise that is.
Bearing in blower motor?
Alternator is defective and needs replacing.
yes but why would you leave it loose?
You might need to flush your power steering fluid system. What causes this whining or sizzling noise is the hydraulic bar getting stuck which a driver doesn't feels in its rack. or if your car recently visited a ditch or hot a side walk really hard, these factors can effect your steering rack and steering Coulomb.
electrical interference
Diff whine
this is normal and nothing to worry about. Almost all vehicles make a whining noise in reverse Ford Mondeo's sound the same reversing as they do going forwards no whining also VW Passatt i think the Golf's are the same also maybe modern technology has improved this. probably bad enough listening to your wife whining you can do without your car doing it.