Earth's Electric Field

In summary, the conversation is about determining the magnitude and polarity of the electric charge on Earth. Measurements show that there is a 100 N/C electric field surrounding the Earth, and the direction of the field lines indicates that the charge is concentrated at the center of the Earth. The formula for calculating the electric field due to a point charge is provided as a hint to find the magnitude of the charge.
  • #1
wikidrox
44
0
I am having trouble doing this question.

Measurements indicate there is an electric field surrounding the earth. Its magnitude is about 100 N/C at the Earth's surface and points to the centre of the earth. What is the magnitude of the electric charge on the earth? Is it positive or negative?
(Hint: The electric field caused by a uniformly charged sphere is the same as if the entire charge were concentrated at its centre)
 
Physics news on Phys.org
  • #2
Look in your book and find out which direction field lines point. Do they leave positive charges and end on negative charges? Or vice versa?

- Warren
 
  • #3
but how do I find the magnitude of the electric charge on earth?
I don't have enought information
 
  • #4
Use the definition of the field due to a point charge. Pretend that all of the Earth's charge is concentrated at a point at the center of the earth. The Earth's radius is 6,378.1 kilometers.

[tex]E = \frac{1}{4 \pi \epsilon_0} \frac{q}{r^2}[/tex]

- Warren
 

What is Earth's electric field?

Earth's electric field is the force exerted by the electric charges in Earth's atmosphere and surface. It is created by the movement of charged particles in Earth's ionosphere and the interaction between the electric field and Earth's magnetic field.

What causes Earth's electric field?

Earth's electric field is primarily caused by the rotation of Earth's liquid metal core, which generates a magnetic field. This magnetic field then interacts with charged particles from the Sun and other sources, creating an electric field.

How is Earth's electric field measured?

Earth's electric field is measured using instruments called electric field meters, which use electrodes to detect the strength and direction of the electric field. These measurements are typically expressed in units of volts per meter (V/m).

Why is Earth's electric field important?

Earth's electric field is important for a variety of reasons. It plays a crucial role in the formation of lightning, which is one of the main mechanisms for balancing the electric charge in Earth's atmosphere. It also helps to protect Earth from harmful charged particles from the Sun.

Can Earth's electric field change?

Yes, Earth's electric field can change in response to various factors such as solar activity, atmospheric conditions, and human activities. For example, solar storms can cause temporary disturbances in Earth's electric field, while human activities such as power plants and power lines can also contribute to changes in the electric field.

Similar threads

  • Introductory Physics Homework Help
Replies
9
Views
149
  • Introductory Physics Homework Help
Replies
12
Views
983
  • Introductory Physics Homework Help
Replies
6
Views
909
  • Introductory Physics Homework Help
Replies
17
Views
326
  • Introductory Physics Homework Help
Replies
7
Views
932
  • Introductory Physics Homework Help
Replies
2
Views
1K
  • Introductory Physics Homework Help
Replies
4
Views
1K
  • Introductory Physics Homework Help
Replies
11
Views
1K
  • Introductory Physics Homework Help
Replies
11
Views
308
Replies
22
Views
1K
Back
Top