oblicz predkość auta o masie 1,5 tony posiadajcego energie kinetyczną 90 kgj (kilo dżule)

[latex]m = 1,5 t = 1500 kg E_k = 90 kJ = 90000 J V = ? E_K = frac{mV^2}{2} 2E_K = mV^2 V^2 = frac{2E_K}{m} V = sqrt{ frac{2E_K}{m} } V = sqrt{ frac{2*90000 J }{1500 kg } } V = 10,96 m/s [J/kg] = [ N*m/kg ] = [kg*m/s^2 * m/kg ] = [m^2/s^2][/latex]

Dane:                                                             Szukane: m=1,5 t= 1500 kg                                             v=? Ek=90 kJ= 90000 J Ek=m*v^2/2 /*2 2Ek=m*v^2 //:m 2Ek/m= v^2 v^2= 2*90000 J/1500 kg v^2=120 m^2/s^2 v=(w zaokrągleniu)10,95 m/s