Measuring the electric field of the Earth

In summary: The electric field of a point charge is determined by the charge's mass and its distance from a point in an electric field.
  • #1
jamie.j1989
79
0
Hi, I'm trying to measure the electric field of the Earth using a simple set up and would just like some opinions on the viability and practicality of this method.

The set up is as follows, two parallel metal plates with one larger than the other, the larger one is placed over the smaller at a separation of d, and an oscilloscope. I plan to ground the lower plate and to insulate the higher plate from ground. The larger plate should acquire a potential of,

$$V_{charge}=\frac{JA}{C}t$$

In a time t.
This result was found at http://arxiv.org/ftp/physics/papers/0701/0701296.pdf page 3 equation (4).

where J is the current density with units $$Amps*m^{-2}$$,A is the area of the plate, C is the capacitance, t the exposure time. I'm assuming here that what they mean by capacitance of the plate is the plates intrinsic capacitance? Which I am unsure about how to calculate.

I then plan to discharge the higher plate to the lower, and obtain a value for $$V_{charge}$$ from the oscilloscope, I will then use

$$\frac{V_{charge}C}{A}=\sigma$$

Where $$\sigma$$ is the charge density of the plate, and

$$\sigma=\epsilon_0E$$

To work out the electric field E of the earth. I'm slightly unsure whether the physics is correct though?

Thanks for any help.
 
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  • #2
It will depend on the distance between the plates and their sizes, but I would expect capacitance to be dominated by the volume between the two plates, similar to a usual parallel plate capacitor.

Looks right.
 
  • #3
A diagram of an electric field mill:

http://rpmedia.ask.com/ts?u=/wikipedia/commons/thumb/9/99/Signalverarbeitung-Feldm%C3%BChle.svg/220px-Signalverarbeitung-Feldm%C3%BChle.svg.png
signal conditioning inside a field mill. ➀ Chopper wheel; ➁ sensor plates; ➂ base plate; ➃ rotary encoder; ➄ drive; ➅ amplifier; ➆ multiplier; ➇ low-pass; ➈ display
http://rpmedia.ask.com/ts?u=/wikipedia/commons/thumb/e/e5/Prinzip-Feldm%C3%BChle.svg/220px-Prinzip-Feldm%C3%BChle.svg.png
 
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Related to Measuring the electric field of the Earth

1. How is the electric field of the Earth measured?

The electric field of the Earth is measured using instruments called electroscopes. These devices use conductive plates and a charged object to detect the strength and direction of the electric field.

2. What is the unit of measurement for the electric field of the Earth?

The electric field of the Earth is typically measured in units of volts per meter (V/m). This represents the amount of electrical potential energy per unit of distance.

3. What factors can affect the electric field of the Earth?

The electric field of the Earth can be affected by various factors, including the Earth's magnetic field, atmospheric conditions, and the presence of objects with different electric charges.

4. How does the electric field of the Earth vary across different locations?

The electric field of the Earth can vary significantly across different locations. This is due to the differences in the Earth's surface and the varying amounts of charge present in different regions.

5. What is the significance of measuring the electric field of the Earth?

Measuring the electric field of the Earth can provide valuable information about the Earth's atmosphere, weather patterns, and even geological activity. It is also important in understanding and predicting the behavior of charged particles in space and their effects on our planet.

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