Concept Simulation 20.4 provides background for this problem and gives you the opportunity to verify your answer graphically. How many time constants (a decimal number) must elapse before a capacitor in a series RC circuit is charged to 65.0% of its equilibrium charge?

Respuesta :

Answer:

The time constant is 1.049.

Explanation:

Given that,

Charge [tex]q{t}= 0.65 q_{0}[/tex]

We need to calculate the time constant

Using expression for charging in a RC circuit

[tex]q(t)=q_{0}[1-e^{-(\dfrac{t}{RC})}][/tex]

Where, [tex]\dfrac{t}{RC}[/tex] = time constant

Put the value into the formula

[tex]0.65q_{0}=q_{0}[1-e^{-(\dfrac{t}{RC})}][/tex]

[tex]1-e^{-(\dfrac{t}{RC})}=0.65[/tex]

[tex]e^{-(\dfrac{t}{RC})}=0.35[/tex]

[tex]-\dfrac{t}{RC}=ln (0.35)[/tex]

[tex]-\dfrac{t}{RC}=-1.049[/tex]

[tex]\dfrac{t}{RC}=1.049[/tex]

Hence, The time constant is 1.049.

The time constant must elapse 1.049 times

Time constant:

Let the charge on the capacitor be q.

The discharge of the capacitor is a function of time as described below:

[tex]q(t)=q_o[1-e^\frac{t}{RC} ][/tex]

where RC is the time constant of the circuit

and q₀ is the initial charge

It is given that the charge left is:

q(t) = 0.65q₀

[tex]q(t)=q_o[1-e^-\frac{t}{RC} ]\\\\0.65q_o=q_o[1-e^{-\frac{t}{RC}} ]\\\\e^{-\frac{t}{RC}}=0.35\\\\\frac{t}{RC}=1.049[/tex]

The time constant elapses 1.049 times.

Learn more about time constant:

https://brainly.com/question/15033402?referrer=searchResults