different types of energy

[tommy666]

certain energies are more... full of energy than others. this probably isnt the right way to explain it but... you know how like... heat energy is more energyful than light energy. um... slightly better way to explain it, you need to use more electrical energy to convert itself into heat energy than you need to produce light energy. just like how light energy costs less than heat energy, because it takes more electrical energy to make the heat than it does to make the light. can someone explain to me

1) the ranking of the "energyfulness" of each energy, eg say elecric is most energyful, then heat then light then radiation energy etc.
2) is radiation energy an energy?
3) what do i actually mean when i say energyfulness? and when i have used my own random made up explanations, what do i actual mean? and whats the techincal way of saying it?
4) why is there like, 500kj of energy in a bag of crisps, but only 0.3joules of energy in a bb gun, and 7kj of energy in a high powered sniper rifle?
5) correct me on whatever you can

[jake-the-peg]

I think you have to realise that how you perceive the energy is related to your senses.

A television transmitter uses a huge amount of energy but we can't sense radio waves so you don't notice. If that energy was light instead it'd be blinding. Unless of course you were blind! in which case you wouldn't notice.

The bag of crisps one is interesting - you don't notice this energy because it's released slowly. I was at the RI Chistmas lectures this year and they demonstrated this by putting the contents of a bag of crisps in liquid oxygen and lighting it. - I was in the balcony about 10m up and the flame was up to my head and you couldn't look at it it was so bright.

So in summary the energy is comparable but we don't always have the senses to appreciate it which is why we use experiments to measure and compare and which is why the results can be surprising

[drjohn]

The previous answer is right in saying it's how you perceive the energy. Also, it is related to what form the energy takes in how you think of it's 'energyfulness', perhaps you may think that a laser has more energy than being slapped across the face with a wet fish.

The important thing here is that a laser pulse containing 100 Joules of energy is just as 'energyful' as a handful of crisps containging 100 Joules of energy. The energy is the same, it's just in what form the energy is contained or released.

For example, in lightbulbs electrical energy is converted into light and heat. In solar panels the energy from the sun's light is converted into electrical energy.

The deomstration of the packet of crips ignited after being soaked in liquid oxygen is a great way of showing the rapid release of energy, the same amount of energy is released if you ate the crisps, albeit in a slower and less dramatic way!