Electric fields- the force exerted on a given charge

In summary, the equation for force in a uniform electric field is F=E/Q, while the equation for the electric field between oppositely charged plates is F=EQ. This is because in a parallel plate capacitor, the electric field is relatively uniform, resulting in a uniform force. However, in a more general situation, the electric field and force may vary depending on the distribution of charges in the area. Coulomb's Law can be used to understand this relationship.
  • #1
leah3000
43
0
why is there a different equation for force in a uniformed electric field F=E/Q as opposed to the electric field between a pair of oppositely charged plates F=EQ ?

I thought it would be the same as the field between a pair of oppositely charged plates are also relatively uniformed, in the centre that is.

also how is the equation F=E/Q when E=F/Q ?:confused:
 
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  • #2
F=qE, in the absence of a magnetic field, as given by the Lorentz force equation.
 
  • #3
F = qE is a general relation. In a parallel plate capacitor E is relatively uniform due to the geometry of charge distribution, so F is uniform.

In a more general situation one must examine how the E field varies in space due to charge distribution in the local region, there E varies in space and F varies too. See Coulomb's Law or a reference on electrostatic fields.
 

1. What is an electric field?

An electric field is a physical quantity that describes the force exerted on a charged particle by other charged particles in its vicinity. It is represented by lines of force and is measured in units of Newtons per Coulomb (N/C).

2. How is an electric field created?

An electric field is created by placing a charged particle, such as an electron or a proton, in a region of space. The charged particle will then exert a force on other charged particles in its vicinity, creating an electric field.

3. How is the strength of an electric field determined?

The strength of an electric field is determined by the magnitude of the charge creating the field and the distance from that charge. The greater the charge and the closer the distance, the stronger the electric field will be.

4. What is the direction of an electric field?

The direction of an electric field is always in the direction that a positive test charge would move if placed in the field. This means that the direction of the electric field is away from positively charged particles and towards negatively charged particles.

5. How does an electric field affect charged particles?

An electric field exerts a force on charged particles, causing them to either accelerate or change direction. The direction of the force is dependent on the charge of the particle and the direction of the electric field. Additionally, the electric field can also cause charged particles to experience repulsion or attraction towards other charged particles.

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