Help With 15.15 & 15.16: A Capacitor + Resistor Circuit

AI Thread Summary
The discussion revolves around solving problems related to a capacitor and resistor circuit connected to a 12 V battery. The initial questions focus on determining the potential difference (p.d.) across the capacitor and resistor, the current, and the charge on the capacitor plates when the switch is first closed and after steady conditions are reached. Participants emphasize the need for the original poster to share their calculations and understanding of key concepts like resistance, current, voltage relationships, and the function of a capacitor. The conversation highlights the importance of grasping these foundational principles to solve the circuit problems effectively. Overall, the thread encourages collaboration and deeper engagement with the material for better comprehension.
CathyLou
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Hi.

I've no idea how to answer the following questions. Could someone please help? I'd really appreciate it.

15.15 A capacitor is joined in series with a resistor, a low resistance microammeter, a switch and a 12 V battery.

(a) When the switch is first closed, what is

(i) the p.d. across the capacitor

(ii) the p.d. across the resistor

(iii) the current

(iv) the charge on each of the capacitor plates?

(b) Calculate also the same quantities when the switch has been closed for some time so that steady conditions have been reached.

(c) If the capacitor had continued to charge at its initial rate, how long would it have taken to become fully charged?

15.16 In the previous question, at a certain instant after the switch has been closed the microammeter reads 9.5 μA. Calculate, for this instant

(a) the p.d. across the resistor

(b) the p.d. across the capacitor

(c) the charge on each of the capacitor plates?


Thank you.

Cathy
 
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well no one will help you unless you give us your work and thougts so far.
 
For (a) (i) I wrote down 12 V, but I'm not sure if this is correct or how to do the next parts.
 
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