Q4_Lesson 1 - Electric Potential Energy in a Uniform Electric Field

Energy

whether it is mechanical, chemical, or electrical, comes in two forms

kinetic and potential

two forms of energy

Potential energy

stored energy of an object at rest

kinetic energy

Potential energy is converted into____when an object moves

True

(T/F) ALL electrical circuits require the storage of energy before transformed into light, heat, and motion

electric potential energy

stored energy in a circuit

accelerates

Once the ball begins to fall off from the table, it _______ and the potential energy is transformed into kinetic energy

Electric charges, mass of objects

_____ in an electric field are comparable to the ____ in a gravitational field

electric potential energy

determines how much stored energy a charge has

Electric potential energy

defined as the energy needed to move a charge against an electric field

conservative forces

Potential energy can only be defined for ___

conservative forces

where the force required to move an object from one position to another is independent of the path taken

Electrostatic force

force required in the interaction of charges

Electrostatic force

example of a conservative force

Electric potential

amount of work required to bring the unit positive charge from infinity to a certain point

electric potential energy

amount of energy required to move a charge against the electric field

Electric force (F)

required to move an electric charge that contains potential energy either towards an opposite charge or against a like charge

U_A > U_B

What can you say about the relative magnitudes of U_A and U_B when the work is positive?

U_A < U_B

What can you say about the relative magnitudes of U_A and U_B when the work is negative?

change in kinetic energies (ΔK)

the total work done is equal to the ____

K_A – K_B

change in kinetic energies (ΔK) formula

The work done expressed in terms of internal energy U,

We can equate the change in K and change in U

Law of conservation of mechanical energy

• W_A→B, J

• U_E, J or Nm

• q₀E, C

• F, N

• r, m

• k, 9.0 ✕ 109 Nm² /C²

• m, kg

• a, m/s²

• P, J/s or W

Symbol and Unit of:

• Work done by force

• Electric potential energy

• Enclosed electric charge

• Force

• Radius

• Coulomb’s constant

• Mass

• Acceleration

• Power

equally distributed parallel, does not change.

In a uniform electric field, the electric field lines are ______ to each other and the

strength of the field ____

work done by the electric field

potential energy for the electric force

work done by the electric force

increases

The potential energy U ____ if the charge q0 moves in the direction opposite of the electric force

decreases

The potential energy U ___ if the charge q0 moves in the direction similar to the electric force

shared property

In some cases, the potential energy U becomes a “___” of two charges

Electric Potential Energy of Two Charges

law of conservation of mechanical energy

when applied to electric charges, refers to the total kinetic and potential energies present in a system

downward

In a uniform electric field, where the strength of the field is not altered, the work done by the electric field is determined by the product of the force magnitude and the displacement component in the ____ direction of the force