Odpowiedzi

2009-12-20T11:43:15+01:00
M = 4t = 4000kg
F = 2kN = 2000N
t = 5s
Ek = ?

a = F/m; a = v/t
F/m = v/t => v = F*t/m
Ek = 1/2 * mv² = 1/2 * m* F²*t²/m² = 1/2 * F²*t²/m
Ek = 1/2 * 2000²*5² / 4000 = 12500J