Hi,
I've been given this question, and i can't get to the answer and it's driving me mad (prob bein very slow!)
So here it is...
A parallel plate, air filled capacitor is connected to a voltage source of constant voltage. The electric field strength between the plates is then 50kV/m. The plate area is 25cm^2. The space between the plates is now filled with a dielectric of relative permittivity 4.0.
Find the charge on the plates of the capacitor
Here's how i have tackled it...
The resultant electric field in the dielectric is 50kV/m.
Get the area in SI units so A = (25*10-2)^2 = 0.0625m^2
Used the formula E= Q / (Er.E0.A )
Rearranged : Q = E.Er.E0.A
with E= 50,000 Er = 4 E0 = 8.85*10^-12
with these values i get Q = 1.1*10^-7
when the correct answer is Q = 4.4*10^-9
Any help on this question would be much appreciated.....
Thanks
I've been given this question, and i can't get to the answer and it's driving me mad (prob bein very slow!)
So here it is...
A parallel plate, air filled capacitor is connected to a voltage source of constant voltage. The electric field strength between the plates is then 50kV/m. The plate area is 25cm^2. The space between the plates is now filled with a dielectric of relative permittivity 4.0.
Find the charge on the plates of the capacitor
Here's how i have tackled it...
The resultant electric field in the dielectric is 50kV/m.
Get the area in SI units so A = (25*10-2)^2 = 0.0625m^2
Used the formula E= Q / (Er.E0.A )
Rearranged : Q = E.Er.E0.A
with E= 50,000 Er = 4 E0 = 8.85*10^-12
with these values i get Q = 1.1*10^-7
when the correct answer is Q = 4.4*10^-9
Any help on this question would be much appreciated.....
Thanks