# Can someone provide worked solution pls

A 10 μF capacitor stores 4.5 mJ of energy.
It then discharges through a 25 Ω resistor.
What is the maximum current during the discharge of the capacitor?
A 1.2 A
B 18 A
C 30 A
D 36 A
Original post by ArifHussain2004
A 10 μF capacitor stores 4.5 mJ of energy.
It then discharges through a 25 Ω resistor.
What is the maximum current during the discharge of the capacitor?
A 1.2 A
B 18 A
C 30 A
D 36 A

Start with an expression for stored energy, solve to give you a voltage. That is the max voltage at the start of the discharge, so sub that into ohm's law to get a corresponding max current.
can u show me how to do it please?
Original post by Mr Wednesday
Start with an expression for stored energy, solve to give you a voltage. That is the max voltage at the start of the discharge, so sub that into ohm's law to get a corresponding max current.
Original post by ArifHussain2004
can u show me how to do it please?

TSR is not a "do my homework" machine, I have suggested a possible method, if you want more help, give it a go and set out your workings.
Original post by ArifHussain2004
A 10 μF capacitor stores 4.5 mJ of energy.
It then discharges through a 25 Ω resistor.
What is the maximum current during the discharge of the capacitor?
A 1.2 A
B 18 A
C 30 A
D 36 A

Original post by ArifHussain2004
can u show me how to do it please?

I would recommend that you go through the following materials:
https://www.ibphysicstutor.net/induction_hl#13
More details note in the google slide

http://hyperphysics.phy-astr.gsu.edu/hbase/electric/capdis.html
Original post by Mr Wednesday
TSR is not a "do my homework" machine, I have suggested a possible method, if you want more help, give it a go and set out your workings.

Unnecessarily passive-aggressive response.
Unnecessarily passive-aggressive response.

How much teaching experience do you have, the art is in giving students what they need to make progress, not what they want. Oh, and just handing out answers is against the TSR rules.
Original post by Mr Wednesday
Start with an expression for stored energy, solve to give you a voltage. That is the max voltage at the start of the discharge, so sub that into ohm's law to get a corresponding max current.
thank you so much for the solution , I got the answer but I wanted to double check why ohms law can be applied to capacitors because I thought there is no resistance in the capacitor ? or are we saying that the Vmax found for the capacitor is exactly the same value as for the resistor so we are actually applying ohms law to the resistor
Original post by 1234kelly
thank you so much for the solution , I got the answer but I wanted to double check why ohms law can be applied to capacitors because I thought there is no resistance in the capacitor ? or are we saying that the Vmax found for the capacitor is exactly the same value as for the resistor so we are actually applying ohms law to the resistor

Note that there is a resistor connected in series with the capacitor.