Electric & Magnetic Fields (7) Flashcards
what is an electric field
a region where a charged particle experiences a force
Do all charged particles create their own electric fields?
yes
How does a repulsive force change with distance?
It decreases as distance increases.
What type of force do electric fields exert?
Electrostatic force.
What is the formula for electric field strength?
E = F/Q
What does the direction of electric field lines indicate?
Away from a positive charge, toward a negative charge.
What is the unit of electric field strength?
Newtons per Coulomb (N/C).
How do you determine the direction of an electric field?
Use a positive test charge as a reference.
What is the formula for electrostatic force?
F=KQ1Q2/r^2
What happens to the force if the distance between charges doubles?
1/4
What does Coulomb’s Law state?
The force between two charges is proportional to their product and inversely proportional to the square of their separation.
What does a positive force indicate?
repulsive force between Q1 and Q2
What is the formula for the electric field due to a point charge?
E=KQ/r^2
How does the electric field strength change with distance?
It follows an inverse square law, decreasing as distance increases.
What type of field does a point charge produce?
a radial field
How is this equation similar to gravitational field strength?
both follow an inverse square law
What is electric potential?
Work done per unit charge in moving a test charge to a point.
How does electric potential change with distance?
It decreases with distance for a positive charge and increases for a negative charge.
What happens to potential energy when a charge moves against an electric field?
It increases.
What does a steeper potential gradient mean?
A stronger electric field.
What is the formula for electric field strength between parallel plates?
E=V/D
what type of field can this be used in
only uniform
What is the direction of the electric field between plates?
From the positively charged plate to the negatively charged plate.
What happens to a charge in a uniform field?
It experiences a constant force.
What is the equation for electric potential in a radial field due to a point charge?
V=KQ/r
How is electric potential different from electric field strength?
Potential varies as 1/r, while field strength varies as 1/r^2
What is the potential at infinity?
zero
The electric potential at a point is defined as:
The work done per unit charge in bringing a positive test charge from infinity to that point
How are electric field lines drawn?
Away from positive charges, towards negative charges.
What do closer field lines indicate?
A stronger electric field.
What happens at a neutral point between two like charges?
The electric field strength is zero.
How do field lines behave in a uniform field?
They are parallel and equally spaced.
