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Capacitor question

Dear forum users, I really need some help on this.

I found that both the discharging AND charging graphs of a capacitor(current against time) have the same shape! I'm absolutely clear about the discharging graph, since discharging means less charge and therefore rate of flow would probably decrease as well. however, when i look at the charging graph..i really have no idea why should the current drop as time increases!! There should be more and more charge building up inside the capacitor..but i sort of thought over it and came out with a conclusion that..as the capacitor gets more and more saturated with charge, the RATE OF FLOW OF CHARGE(which is the current)decreases, even though the amount of charge stored inside has accumulated to a high level. Am i right?

TO conclude: Is it right for me to put forward the following statements:

1. When the capacitor discharges, the amount of charge in the capacitor decreases, with the rate of flow of charge out of the capacitor decreasing, resulting in a drop in current as time proceeds.

2. When the capacitor charges up, the amount of charge in the capacitor increases, BUT the rate of flow of charge INTO the capacitor slows down, therefore results in a drop in current as time goes, which then gives us the same graph as the one we get from a discharging capacitor.

I'm sorry to cram so many words in one post, but i really need to clarify my thoughts. I've been pondering on this subtopic for about 2 weeks already..

Reply 1

Drummy

strictly speaking if the current charging the capacitor is positive then the discharge current is negative as its in the opposite direction.

when the capacitor starts to charge it does so quickly as there is little opposition from the charge already on the plates. As time goes by there is more and more opposition so the rate of increase of charge (the current) decreases.
Experiment - See how many cream cakes you can eat. How quickly can you do it?

when the capacitor starts to discharge it does so quickly as the force pushing the charge off is big because there's a lot of it there. The rate of decrease of charge (the current) is big. As time goes by there is less charge on the plates so this gets smaller.
Experiment - now vomit the cream cream cakes you ate earlier. How quickly do they come out?