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Now we all know it's boring to just hear laws and rules about energy, so let's get
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our hands dirty with a good story. It starts when radiant energy from the sun
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reaches the earth's atmosphere. We know that it gets hotter and some of that
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energy is used by plants for photosynthesis. Then the plants photosynthesise and turn the
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radiant energy into glucose, which is chemical energy.
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The lettuce starts getting bigger but you're hungry, so you pick the lettuce.
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And since your body is warm from the radiant energy in the atmosphere, and all the lettuce
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picking, you decide to have something cold for lunch: a salad!
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The chemical energy that is still stored in the lettuce is transferred to your body.
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Now you feel strong! So you decide to get on your bicycle and go
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for a ride. As you pedal, the chemical energy from the
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lettuce turns into kinetic energy in your legs, causing the bicycle to move.
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Some of the kinetic energy is converted to thermal energy, which is why you get warm
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after pedaling for a while. After converting all this chemical energy
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into kinetic and thermal energy, you return home.
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It's simple. Energy is moving from the sun, to the lettuce,
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to your body and then used to pedal the bicycle. But when you get home, it's dark already,
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so you turn on your dynamo. The dynamo, or generator, produces electrical
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energy to power your house as well as thermal energy to warm you up.
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Some of that electrical energy will then be used when you turn on your stove to cook dinner.
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The electrical energy is then converted to thermal energy to cook your food.
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So as you can see, the flow of energy keeps going on and on, with energy converting between
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different forms throughout a regular day. Even as you watch this, you are using chemical
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energy that you accumulated from everything you ate today.
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It's a never-ending process! And that's an example of how energy is converted
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between different forms. So the next time you do a series of actions
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think about how energy is being converted. You'll be amazed at what you discover!