Energy can be transferred from one form to another, but I’m not sure how to visualize what it looks like when this happens. For example, what would the kinetic energy of a moving car look like if all the energy (perfectly converted) was heat, sound, or light?
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What do you mean by “perfectly converted”? There is no such real thing as conversion to only one other type of energy, so there’s no way to visualize that. Energy is converted all the time, just not 100% of it. In your car kinetic energy example, it’s converted to sound through screeching tires, through whooshing air, through vibrating engines, and it’s converted to heat through friction between the car and air, and the friction between the tires and the road. There isn’t really any light being created.
energy is the ability to do work. it comes in many forms, such as heat, light, sound, electricity and chemical energy.
A car traveling at 30mph has about 130 kilojoules.
That’s enough heat to raise about a pound of water up to boiling. So… Not even enough to cook noodles.
Temperature is usually a REMARKABLE amount of energy.
Sound and light are hard to compare. That’d equal a very dangerous blinding laser running for 35 hours.
In gasoline, chemical potential, that’s 2.7 grams, or a less than a shot.
Rather than consider energy, consider power.
Energy can be built up and stored. It’s not really fair to compare as some things happen gradually and some happen instantaneously.
Power is instantaneous energy rate. Energy divided by time.
100W is using 100J per second.
So I’m on mobile and don’t have exact numbers to hand. Here’s some basic ones off the top of my head:
Cycling hard on a bike would be at least 500W for most people. A car’s engine would easily be 100kW (100,000W).
An led ligttbulb might be 5W, an old filament one maybe 100W (the old ones are really inefficient and actually produce loads of heat instead of pure light)
A laser strong enough to damage your eyes could be 1mW (0.001W).
An electric room heater would be 500-1000W.
An electric shower that instantly heats cold water would generally be around 8kW.
A kitchen blender can be anything from 200-1000W.
A kettle would be 1-2kW.
The energy of a car travelling at 100kmph is around 770kJ. That’s equivalent to the chemical energy of about 33 peanuts, or the radiation energy of sunlight shining on the car for 1/14th of a second. Or the energy to get a 2.25L bottle (like the big plastic coke bottles) of water from room temp to boiling.
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