AnnaLinnea
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Hello all,
I'm new to the forum so I hope I'm posting this in the correct section.
I'm currently conducting an experiment in which I'm examining how the dielectric constant of a binary mixture changes with concentration and temperature using a parallel plate capacitor for measurements. The only problem, however is that the multimeter I'm using doesn't measure capacitance. Here's what I can measure:
• DC volts
• AC volts
• DC current
• AC current
• Resistance
• Temperature
• Frequency
My advisor for this project initially suggested that I find the conductance (or conductivity?) in order to calculate the dielectric constant, however I've searched and searched but I can't seem to find a way to relate the two.
Here's what I got so far.
I know that conductivity can be used to calculate the imaginary part of the dielectric constant
\kappa=\epsilon'+j\epsilon''
\kappa=\epsilon'+j\sigma/\omega
where \kappa is the dielectric constant, \sigma is the conductivity and \omega is the frequency.
but I'm not sure how I would find the real part \epsilon'in order to get \kappa
I've also got the equations
C=Q/V
C=\kappa\epsilon_{0}\frac{A}{d} where \epsilon_{0} is the vacuum permittivity, A is the area of the plate and d is the distance between the plates.
Then for conductivity,
J=\sigma E
G=\sigma\frac{A}{d}
where J is the current density and G is the conductance
and so relating the two
C=\kappa\epsilon_{0}\frac{G}{\sigma}
but that still leaves me with two unknowns, C and \kappa
I feel like there's a really simple, really obvious solution that I'm just not seeing...
Can anybody help me out?
I'm new to the forum so I hope I'm posting this in the correct section.
I'm currently conducting an experiment in which I'm examining how the dielectric constant of a binary mixture changes with concentration and temperature using a parallel plate capacitor for measurements. The only problem, however is that the multimeter I'm using doesn't measure capacitance. Here's what I can measure:
• DC volts
• AC volts
• DC current
• AC current
• Resistance
• Temperature
• Frequency
My advisor for this project initially suggested that I find the conductance (or conductivity?) in order to calculate the dielectric constant, however I've searched and searched but I can't seem to find a way to relate the two.
Here's what I got so far.
I know that conductivity can be used to calculate the imaginary part of the dielectric constant
\kappa=\epsilon'+j\epsilon''
\kappa=\epsilon'+j\sigma/\omega
where \kappa is the dielectric constant, \sigma is the conductivity and \omega is the frequency.
but I'm not sure how I would find the real part \epsilon'in order to get \kappa
I've also got the equations
C=Q/V
C=\kappa\epsilon_{0}\frac{A}{d} where \epsilon_{0} is the vacuum permittivity, A is the area of the plate and d is the distance between the plates.
Then for conductivity,
J=\sigma E
G=\sigma\frac{A}{d}
where J is the current density and G is the conductance
and so relating the two
C=\kappa\epsilon_{0}\frac{G}{\sigma}
but that still leaves me with two unknowns, C and \kappa
I feel like there's a really simple, really obvious solution that I'm just not seeing...
Can anybody help me out?