Physics
Is it practically possible to convert a form of energy completely into another useful form? Give reason.
Answer
No. In real life we can’t convert one form of energy completely into another useful form. Some energy is always lost (dissipated) to the surroundings as heat, sound, vibration, friction, etc., so efficiency is always less than 100%. For example, an electric bulb gives light but also produces heat; a car engine changes fuel energy into motion but lots becomes heat and sound. Total energy is conserved, but not all of it stays in a form we can use.
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