A charged capacitor is connected to an ideal inductor. At time t = 0, the charge on the capacitor is equal to 6.00 μC. At time t = 2.00 ms the charge on the capacitor is zero for the first time. What is the amplitude of the current at that same instant?

Respuesta :

Answer:

[tex]4.71\times 10^{-3}A[/tex]

Explanation:

[tex]Q_{max}[/tex] = Maximum charge stored by capacitor = 6 μC = 6 x 10⁻⁶ C

[tex]t[/tex]  = time taken for charge on the capacitor to become zero = 2 ms = 2 x 10⁻³ s

Time period is given as

[tex]T = 4t[/tex]

[tex]T = 4(2\times 10^{-3})[/tex]

[tex]T = 8\times 10^{-3} s[/tex]

Angular frequency is given as

[tex]w = \frac{2\pi }{T}[/tex]

[tex]w = \frac{2(3.14) }{8\times 10^{-3}}[/tex]

[tex]w[/tex] =785 rad/s

Charge at any time is given as

[tex]Q(t) = Q_{max}Coswt[/tex]

Taking derivative both side relative to "t"

[tex]\frac{\mathrm{d}Q(t) }{\mathrm{d} t} = \frac{\mathrm{d}(Q_{max}Coswt) }{\mathrm{d} t}[/tex]

[tex]i(t)= -Q_{max} w Sinwt[/tex]

Amplitude of the current is given as

[tex]i_{max}= Q_{max} w[/tex]

[tex]i_{max}= (6\times 10^{-6}) (785)[/tex]

[tex]i_{max}= 4.71\times 10^{-3}A[/tex]