Odpowiedź :
Odpowiedź:
zad. 1
P = 600 W
t = 3 min = 3*60s = 180 s
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W = ?
W = P*t = 600W*180s = 108 000 J = 108 kJ
W = 108 kJ
zad. 2
h =1,6 m
m = 5t = 5*1000kg = 5000 kg
g = 10/m/s2
t = 8 h = 8*3600s = 28 800 s
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P = ?
Ep = mgh = 5000kg*10m/s2*1,6m = 80 000 J
Ep = W
W = P*t
P = W/t= 80000J/28800s = 25/9 W ≈ 2,78 W
Pśr = 2,78 W
1.
[tex]dane:\\P = 600 \ W\\t = 3 \ min = 3\cdot60 \ s = 180 \ s\\szukane:\\W = ?\\\\P = \frac{W}{t} \ \ /\cdot t\\\\W = P\cdot t\\\\W = 600 \ W\cdot180 \ s\\\\W = 108 \ 000 \ J = 108 \ kJ[/tex]
2.
[tex]dane:\\m = 5 \ t = 5 \ 000 \ kg\\h = 1,6 \ m\\t = 8 \ h = 8\cdot3600 \ s = 28 \ 800 \ s\\g = 10\frac{N}{kg}\\szukane:\\P = ?\\\\W = E_{p} = mgh = 5000 \ kg\cdot10\frac{N}{kg}\cdot1,6 \ m = 80 \ 000 \ J\\\\P = \frac{W}{t}\\\\P = \frac{80000 \ J}{28800 \ s} = 2,(7) \ W \approx2,8 \ W[/tex]