Odpowiedź:
Wyjaśnienie:
F = ma
stąd a = F/m
Prędkość:
v = v₀ + a * t
dla 0 < t ≤ 2
F = 4N ==> a = 4/1 = 4 [tex]\frac{m}{s^2}[/tex]
v₀ = 0
v = 0 + 4t = 4 t
[tex]v_k[/tex] = 4*2 = 8 [tex]\frac{m}{s}[/tex]
dla 2 < t ≤ 4
F = 0N ==> a = 0 [tex]\frac{m}{s^2}[/tex]
v₀ = 8 [tex]\frac{m}{s}[/tex]
v = 8 + 0t = 8
[tex]v_k[/tex] = v₀= 8 [tex]\frac{m}{s}[/tex]
dla 2 < t ≤ 4
F = 2N ==> a = 2/1 = 2 [tex]\frac{m}{s^2}[/tex]
v₀ = 8 [tex]\frac{m}{s}[/tex]
v = 8 + 1t = t + 8
[tex]v_k[/tex] = 8 + 2*1 = 10 [tex]\frac{m}{s}[/tex]
