# How Can 1 Watt =1000v ???

Discussion in 'General Electronics Discussion' started by roonyroo, Sep 11, 2012.

1. ### roonyroo

13
0
Jul 13, 2012
Im still trying to understand how electricity works ...

From what I understand Volts is the initial energy or power of a current

Watts is the amount of energy which travels per second

& Amps is the amount of electricity stored

So 1 watt is the speed of electricity travelling, not the actual amount of energy travelling through a wire?

9
0
Sep 1, 2012
3. ### Harald KappModeratorModerator

10,385
2,270
Nov 17, 2011
Sorry, your understanding is not to the point.

Volt is the unit to express voltage which is the potential difference between two points (e.g. two poles of a battery). The more voltage, the higher the potential difference. Voltage alone, however, is no measure for power. Compare this to the pressure in a water system. Pressure alone does not do any work. Only if there is movement of water involved will there be work.
Which leads me to the next point: current. Current is the flow of electrons within e.g. a wire. Current is measured in amperes. Coming back to my above analogy compare current to the amount of water flowing per second through the water system. Lots of water is equivalent to lots of current. Still, Current alone is no measure of power. Lots of current without voltage means no work done. Take the water example: If you have a flow of water no work will be done unless this water works against an obstacle (e.g. a turbine) where a pressure will develop. In this case we have lfowing water (current) and pressure (voltage). Only´the can work be done.
Which again leads me onward to the concept of resistance. Let us ignore the more exotic aspects of supraconducters and the like. Electrons moving through a medium (current through a wire) are constantly opposing the atoms of the medium. This hinders the flow of electrons. The effect is called resistance and can be expressed by Ohm's law: Resistance = Voltage/Current.

We now have a voltage that exerts pressure on the electrons causing a current to flow against the resistance of a wire. You get the concept?

As you are surely aware the current through the wire causes energy to be converted from electrical energy to heat (I'll deliberately ignore motors and lamps for the moment). The more energy is converted, the more heat is generated. This power is expressed in units of Watt (symbol W). 1 W is defined as the product of 1A*1V. Or equivalently 0.5A*2V etc. The absolute value of voltage or current is irrelevant as long as the product stays the same. Going back to the water analogy: You can drive a turbine either with little water that has high pressure (e.g. falling from great height) or with a lot of water at low pressure (e.g. from a flowing river).
Of course you can also have lots of water falling from great height making for much more power or you can have little water (from a small rivulet) at low speed making for much less energy.

None of these concepts has anything to do with the storage of energy.

I hope this explanation is helpful to you.

10,385
2,270
Nov 17, 2011
5. ### keraynopoylos

9
0
Sep 1, 2012
Our messages were posted 5 minutes apart and it definitely took you more than 5mins to type your explanation, so you couldn't have seen it.

6. ### davennModerator

13,654
1,888
Sep 5, 2009
No, Watts = Volts x Amps, it has nothing to do with the "speed" the electricity is travelling as that is relatively constant.