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3 years ago

Zad. 1. Jaką pracę wykona dźwig, który pracował przez 1,5 h napędzany silnikiem o mocy 200 kW?

Physics

1 answer:

Alekssandra [29.7K]3 years ago

7 0

Answer:

Explanation:

1) Moc to wskaźnik czasu pracy w stosunku do czasu.

Moc = czas pracy / czas

Czas pracy = moc * czas

Podana moc = 200 kW = 200 000 Watów

Czas = 1,5 godziny = 1,5 * 3600 = 5400 sekund

workdone = 200 000/5400

Obróbka = 37,04 dżula

2) Moc = Gotowe / czas

Od zakończenia = Siła * Odległość

Moc = siła * Odległość / czas

Podana siła = 300 N.

Odległość = 2,5 m

czas = 0,5 min = 0,5 * 60 = 30 sekund

Moc = 300 * 2,5 / 30

Moc = 25 watów

3) Moc = Gotowe / czas

Czas potrzebny = praca / moc

Biorąc pod uwagę pracę wykonaną przez ciągnik = 10 MJ = 10 * 10 ^ 6 Dżuli

Moc = 100 kW = 100 000 watów

Czas wzięty = 10 ^ 7/10 ^ 5

Zajęty czas = 100 sekund

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