- #1
Jamessamuel
- 45
- 0
Homework Statement
A 12V DC supply is connected in series to 2 capacitors, of 12 and 4 micro farads. A switch is in series also. The diagram shows the capacitors above the supply and the larger capacitance capacitor to the left. The names of the plates of the capacitors from left to right are as follows, A,B,C and D. the + end of the supply is on the left,
i) describe and justify the direction of electron flow when the switch is closed
ii) work out the total capacitance of the arrangement
iii) deduce the charges on each plate when the switch has been closed for some time. justify your answers.
iv) if a 1 megaohm resistor was placed between B and C, how would this affect your answers to i and ii
2. Relevant equations
The Attempt at a Solution
Part i) as the supply establishes a negative potential at end D and a positive at end A, the electrons are moved anticlockwise so as to establish a negative charge at D.
ii) was fine
iii) i think this is where my knowledge of capacitors is strained.
i thought that all the charge moved from A to D. and since the electrons in between B and C are iscolated there isn't a change. This is really where i need help.
iv) naturally my inability to answer the previous part pays no dividends here.
Help would be appreciated.