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yawa3891 [41]
3 years ago
7

un motor electric efectueaza un lucru mecanic de 864 j in 0.5 min.tensiunea la bornele sale este de 12v si este parcurs de un cu

rent de 3a.randamentul motorului este de cat?
Physics
1 answer:
GrogVix [38]3 years ago
3 0

Answer:

96%

Explanation:

To find the values of the motor efficiency you use the following formula:

E=\frac{P_o}{P_i}100

P_o: output power = 864J/0.5min=864J/30s=28.8W

P_i: input power = I*V = (3A)(12V) = 36W

By replacing this values you obtain:

E=\frac{28.8W}{30W}*100=96\%

hence, the motor efficiency is about 96%

traslation:

Pentru a găsi valorile eficienței motorului, utilizați următoarea formulă:

P_o: putere de ieșire = 864J / 0.5min = 864J / 30s = 28.8W

P_i: putere de intrare = I * V = (3A) (12V) = 36W

Înlocuind aceste valori obțineți:

prin urmare, eficiența motorului este de aproximativ 96%

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