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3 years ago

Question#7:a) A television uses 1500J of electric energy to produce 1100J 1 point

Physics

1 answer:

Vesnalui [34]3 years ago

4 0

Answer:

a.73.3%

b.26.6%

Explanation:

a. The efficiency is the energy output, divided by the energy input, and expressed as a percentage.

#Given the energy input as 1500J and the subsequent output as 1100J, the TV's efficiency is calculated as:

$\eta=\frac{E_o}{E_i}\\\\=\frac{1100}{1500}\times 100\%\\\\=73.33\%$

Hence, the TV has an efficiency of 33.3%

b. From a above, we know that the TV has an output of 1100J and input of 1500J.

-We therefore calculate it's wastage as the difference between output and input:

Wastage=Energy Input-Energy Output=1500J-1400J=400J

$E_w=\frac{E_{wasted}}{E_i}\times 100\%\\\\=(400/1500)\times100\%\\\\=26.67\%$

Hence, the TV has wasted of 26.6%

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Answer:

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Explanation:

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Answer:

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