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# What does this mean?? Watch

1. A typical filament lamp is 8% efficient. what does this mean??
2. That it is not very efficient.
3. (Original post by Pitt1988)
That it is not very efficient.
do you like it does provide enough energy or its 8% energy saver
4. It probably means that a lot of the energy expenditure is lost through heat or something.
5. It means 8% of the total energy which went into the machine, in this case the lamp, was converted to useful energy ie: light

It is derived from the equation:

Efficiency = Useful Energy Output/Total Energy Output

Where the output of a machine is never greater than 1
6. It means that 8% of the taken in energy (in this case elevtricity) was converted into useful energy (remember that energy cannot be created or destroyed, only changed). In this case, 8% of the taken in electricity was converted into light, which is the useful energy conversion as the purpose of the lamp is to provide light.

The other 92% of the electricity was wasted. This means that it was converted into energy that was not useful for the purpose of the product (remember, energy can never be destroyed, only changed). In this case the other 92% is likely to be heat.
7. It could lose heat?
8. (Original post by ConorF)
It means 8% of the total energy which went into the machine, in this case the lamp, was converted to useful energy ie: light

It is derived from the equation:

Efficiency = Useful Energy Output/Total Energy Output

Where the output of a machine is never greater than 1
can you help me with another question >>?

Updated: April 16, 2012
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