Bonjour,
Ex 3
1)
20 ms = 20x10^-3 s.
[tex]f = \frac 1T\\
f = \frac{1}{20\times 10^{-3}}\\
f = 50 \text{ Hz}[/tex]
2)
[tex]T = \frac{1}{f}\\
T = \frac{1}{400}\\
T = 2{,}50\times 10^{-3}\text{ s} = 2{,}50 \text{ ms}[/tex]
Ex 8
1)
[tex]U = \frac{U_{max}}{\sqrt 2}\\
U = \frac{15}{\sqrt 2}\\
U = 11 \text{ V}[/tex]
2)
[tex]U_{max} = \sqrt 2 U\\
U_{max} = 6\sqrt 2\\
U_{max} = 8\text{ V}[/tex]
Si tu as des questions, n'hésite pas ! =)
