Question

A capacitor that is initially uncharged is connected in series with a resistor and an emf source with E=110V and negligible internal resistance. Just after the circuit is completed, the current trhough the resistor is 6.5*10^-5A. the time constant for the circuit is 4.8s.
1) What is the resistance of the resistor?
2) What is the capacitance of the capacitor?

Answer 1

Answer:

1

  $R = 1.692*10^{6} \Omega$

2

  $C = 2.837 *10^{-6} \ F$

Explanation:

From the question we are told that

    The voltage is  $E = 110 \ V$

     The current is  $I = 6.5 *10^{-5} \ A$

     The time constant is  $\tau = 4.8 \ s$

The resistance of resistor is mathematically evaluated as

      $R = \frac{E}{I}$

substituting values

      $R = \frac{ 110 }{ 6.5*10^{-5}}$

      $R = 1.692*10^{6} \Omega$

The  capacitance of the capacitor is mathematically represented as

        $C = \frac{\tau}{R}$

substituting values

       $C = \frac{ 4.8}{ 1.692*10^{6}}$

       $C = 2.837 *10^{-6} \ F$