Our newest member to the MAKE-IT-WORK Team is a close friend of mine, David. He is very knowledgeable in math and science. Hi first post I think is great and very informative.
welcome to the team, Dave!
~Matt~
Obviously, to understand the full concept of this equation, you would need to take advanced mathematics and physics classes, but I'll try to explain it as simply as possible. First off, I think we need to understand what the E=mc2 means.
E=energy (measured in Joules, or J)m=mass (measured in kilograms, or k)c=the speed of light (measured in metres per second, or ms-1)So, basically the equation is: Energy=mass multiplied by the speed of light squared.
The speed of light is very close to 186,300 miles per second(300,000 km per second.) In order to make the equation "work" we need to convert the speed of light into units that are better suited to our purposes. In physics, speeds are measured in metres per second. This is usually abbreviated to ms-1; that is "metres times seconds to the minus one". Don’t worry if you don’t understand this notation. We could also write m/s, but using ms-1 makes the math easier. Likewise, we could either say that the speed of light is 300,000,000 metres per second, or, as is more usual, express the same figure in scientific notation: 3 x 108 ms-1.
Now that we have everything in order let’s have a go at solving the equation. We will use a mass of 1kg to keep things simple and I will show all of the workings of the equation. So, with 1kg of mass(around 2.2 pounds) we get:
E=1kg x (3x108 ms-1)2
E=1kg x (3x108 ms-1) x (3x108 ms-1)
E=1 x (9x1016)kg m2s-2
E=9 x 1016 J
Note how the units were dealt with and that kg m2 s-2 is the same as joules. So from 1kg of matter, any matter, we get 9 x 1016 joules of energy. Writing that out fully we get 90,000,000,000,000,00 joules of energy. That is a lot of energy! For example, if we converted 1kg of mass into energy and used it all to power a 100-watt light bulb how long could we keep it lit for? In order to answer the question the first thing to do is divide the result by watts (1 watt is 1 joule per second): 9 x 1016 J / 100W= 9 x 1014 seconds. How long would that be in years? A year is 31,557,600 seconds, so we get:
9 x 1014 seconds / 31,557,600=28,519,279 years.
So we see that 1 kilogram of mass can power a 100-Watt light bulb for 28,519,279 years.
-Dave
welcome to the team, Dave!
~Matt~
E=energy (measured in Joules, or J)m=mass (measured in kilograms, or k)c=the speed of light (measured in metres per second, or ms-1)So, basically the equation is: Energy=mass multiplied by the speed of light squared.
The speed of light is very close to 186,300 miles per second(300,000 km per second.) In order to make the equation "work" we need to convert the speed of light into units that are better suited to our purposes. In physics, speeds are measured in metres per second. This is usually abbreviated to ms-1; that is "metres times seconds to the minus one". Don’t worry if you don’t understand this notation. We could also write m/s, but using ms-1 makes the math easier. Likewise, we could either say that the speed of light is 300,000,000 metres per second, or, as is more usual, express the same figure in scientific notation: 3 x 108 ms-1.
E=1kg x (3x108 ms-1)2
E=1kg x (3x108 ms-1) x (3x108 ms-1)
E=1 x (9x1016)kg m2s-2
E=9 x 1016 J
Note how the units were dealt with and that kg m2 s-2 is the same as joules. So from 1kg of matter, any matter, we get 9 x 1016 joules of energy. Writing that out fully we get 90,000,000,000,000,00 joules of energy. That is a lot of energy! For example, if we converted 1kg of mass into energy and used it all to power a 100-watt light bulb how long could we keep it lit for? In order to answer the question the first thing to do is divide the result by watts (1 watt is 1 joule per second): 9 x 1016 J / 100W= 9 x 1014 seconds. How long would that be in years? A year is 31,557,600 seconds, so we get:
9 x 1014 seconds / 31,557,600=28,519,279 years.
So we see that 1 kilogram of mass can power a 100-Watt light bulb for 28,519,279 years.
-Dave
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