Heat of fusion and vaporisation must also be taken into account. Power is also a time-dependent value.
Thus:
Energy required = (mass * specific heat capacity * deltaT) + (mass * heat of fusion) + (mass * heat of vaporisation)
Power = Energy/Time, and is measured in watts.
With one kilogram of iron, initially at 20 degrees celsius (given that steel is a compound)
difference = 2841 degrees celcius.
time to vaporise one kilogram = 10 seconds
This is not dissimilar power to a lightning strike or a small nuclear power plant. Unlike either, the lightsaber is very small, and unlike the nuclear power station, has no obvious cooling systems. Furthermore, if one reduces the time to vaporise to one second, the power output reaches 7.6 gigawatts, compared with a large nuclear power station's peak output of about 2 gigawatts.
Note that no energy losses are taken into account here - all of the power is transferred directly to the kilogram of iron, and the decrease of transfer rate as the kinetic energy of the iron increases.
These sums may or may not be accurate. I suspect they're in the appropriate regions, but my source disagrees with itself in several locations.
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Eek! Hadn't noted that one. My apologies to all...
Heat of fusion and vaporisation must also be taken into account. Power is also a time-dependent value.
Thus:
Energy required = (mass * specific heat capacity * deltaT) + (mass * heat of fusion) + (mass * heat of vaporisation)
Power = Energy/Time, and is measured in watts.
With one kilogram of iron, initially at 20 degrees celsius (given that steel is a compound)
difference = 2841 degrees celcius. time to vaporise one kilogram = 10 seconds
E=(1 * 449 * 2841) + (1 * 247000) + (1 * 6090000) E= 1275609 + 247000 + 6090000 E= 7612609 J
Power = 7612609/10 = 761 megawatts
This is not dissimilar power to a lightning strike or a small nuclear power plant. Unlike either, the lightsaber is very small, and unlike the nuclear power station, has no obvious cooling systems. Furthermore, if one reduces the time to vaporise to one second, the power output reaches 7.6 gigawatts, compared with a large nuclear power station's peak output of about 2 gigawatts.
Note that no energy losses are taken into account here - all of the power is transferred directly to the kilogram of iron, and the decrease of transfer rate as the kinetic energy of the iron increases.
These sums may or may not be accurate. I suspect they're in the appropriate regions, but my source disagrees with itself in several locations.