A capacitor with an initial potential difference of 100 V isdischarged through a resistor when a switch between them is closed at t ! 0.At t ! 10.0s,the potential difference across the capacitor is 1.00V. (a) What is the time constant of the circuit? (b)What is the potential difference across the capacitor at t ! 17.0s?

Respuesta :

Answer:

(a). The time constant of the circuit is 2.17.

(b). The potential difference across the capacitor at t=17.0 s is 0.0396 V.

Explanation:

Given that,

Initial potential difference = 100 V

Potential difference across the capacitor = 1.00 V

(a). We need to calculate the time constant of the circuit

Using formula of potential difference

[tex]V(t)=V_{0}e^{\dfrac{-t}{RC}}[/tex]

Put the value into the formula

[tex]1.00=100e^{\dfrac{-10.0}{RC}}[/tex]

[tex]0.01=e^{\dfrac{-10.0}{RC}}[/tex]

On taking ln

[tex]ln(0.01)=\dfrac{-10}{RC}[/tex]

[tex]RC=\dfrac{-10}{ln(0.01)}[/tex]

[tex]RC=2.17[/tex]

(b). We need to calculate the potential difference across the capacitor at t=17.0 s

Using formula again

[tex]V(17)=100e^{\dfrac{-17}{2.17}}[/tex]

[tex]V{17}=0.0396\ V[/tex]

Hence, (a). The time constant of the circuit is 2.17.

(b). The potential difference across the capacitor at t=17.0 s is 0.0396 V.

Lanuel

Based on the calculations, the time constant of this circuit is equal to 2.172.

Given the following data:

Initial potential difference = 100 V.

Initial time = 10 seconds.

Final time = 17 seconds.

Final potential difference = 1.00 V.

How to calculate the time constant of a circuit.

Mathematically, potential difference is given by this formula:

[tex]V(t)=V_oe^{\frac{-t}{RC} }\\\\1=100e^{\frac{-10}{RC} }\\\\\frac{1}{100} =e^{\frac{-10}{RC} }\\\\0.01=e^{\frac{-10}{RC} }\\\\ln(0.01)={\frac{-10}{RC} }\\\\-4.6051={\frac{-10}{RC} }\\\\RC=\frac{-10}{-4.6051} \\\\[/tex]

RC = 2.172.

How to calculate the potential difference.

Time, t = 17.0 seconds.

[tex]V(t)=V_oe^{\frac{-t}{RC} }\\\\V(17)=100e^{\frac{-17}{2.172} }\\\\V(17)=100e^{-7.8269} }\\\\V(17)=100 \times 0.0003989[/tex]

Potential difference = 0.03989 Volt.

Read more on potential difference here: brainly.com/question/4313738

Q&A Education