[tex]\displaystyle \\
\texttt{Folosim formula: } \\
E = P \times t \\
unde: \\
E = 480 ~Wh = Energia \\
P = 1,2 ~KW = 1200~W = Puterea \\
t = ?~ore = Timpul \\
Rezolvare: \\ \\
t = \frac{E}{P} = \frac{480 ~Wh}{1200W} = \frac{2 ~Wh}{5 W} = \frac{2 }{5 }~ ore = \frac{2\times 60 }{5 }~min = \boxed{24 ~min }[/tex]