The total power input to the LED was 0.24 W.

Physics

1 answer:

just olya [345]2 years ago

4 0

Answer: How do you calculate useful power output?

Explanation: Hence, useful energy output:

Wuseful=F×d=10×5=50 J W useful = F × d = 10 × 5 = 50 J. ...

Ewasted=65−50=15 J E wasted = 65 − 50 = 15 J. ...

Efficiency=Useful energy outputTotal energy input×100%=5065×100%=76.9% Efficiency = Useful energy output Total energy input × 100 % = 50 65 × 100 % = 76.9 %

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