Poproszę o zadanie 5. Z wszystkimi wzorami bym prosił :)

[latex]3.\ P= frac{W}{t} \ t= frac{W}{P} =frac{480J}{6W} =80 s\ 4.\ v= sqrt{2gh} \ h= frac{v^2}{2g} =frac{36m^2/s^2}{2*10m/s^2} =1,8 m\ 5.\ v=108km/h=30m/s\ E_m=E_p+E_k=mgh+ frac{mv^2}{2} =2kg*10m/s^2*80m+ frac{2kg*900m^2/s^2}{2} =\ 2500J\ 6.\ v=36km/h=10 m / s\ W=E_1_k-E_2_k= frac{1000kg*400m^2/s^2}{2}- frac{1000kg*100m^2/s^2}{2} =150000J\ [/latex]

[latex]5.\dane:\m = 2 kg\h = 80 m\v = 108frac{km}{h} = 108cdotfrac{1000m}{3600s} = 30frac{m}{s}\g = 10frac{m}{s^{2}} = 10frac{N}{kg}\szukane:\E_{m} = ?[/latex] [latex]E_{m} = E_{p} + E_{k}\\E_{p} = mgh = 2kgcdot10frac{N}{kg}cdot80m = 1 600 J\\E_{k} = frac{mv^{2}}{2} = frac{2kgcdot(30frac{m}{s})^{2}}{2} = 900 J\\E_{m} = 1600 J + 900 J = 2 500 J = 2,5 kJ[/latex] Odp. Energia mechaniczna ptaka wynosi 2 500 J (2,5 kJ).