Term
| electrostatic force is a nonconsevative or a conservative force? |
|
Definition
|
|
Term
as particle accelerates from point a to point b is the potential energy decreasing or increasing?
what about KE? |
|
Definition
potential energy is decreasing
KE is increasing by an equal amount |
|
|
Term
given a positive & negative plate
+ -
+ -
+ -
+ -
+ -
1.where will the postive charge,q, have :
the highest potential energy
2.where will the negative charge,q, have :
the highest potential energy?
|
|
Definition
1.at the positive plate
2. at the negative plate |
|
|
Term
| what is Electric potential ? |
|
Definition
potential energy per unit charge |
|
|
Term
| what are Equipotential Lines |
|
Definition
| equipotential is a line or surface over which the potential is constant. |
|
|
Term
Electric field lines are _____ (direction) to equipotentials. |
|
Definition
|
|
Term
| The surface of a conductor is an usually made up of |
|
Definition
|
|
Term
| what is an electron volt (eV) ? |
|
Definition
| the energy gained by an electron moving through a potential difference of 1 volt. |
|
|
Term
potential vs electric field which is a scalar quantity, which is a vector? |
|
Definition
potential: scalar
electrical field: vector |
|
|
Term
| The potential due to an electric dipole is equal to |
|
Definition
the sum of the potentials due to each charge,
and can be calculated exactly |
|
|
Term
|
Definition
| two equal point charges (Q )of opposite signs that are seperated by a distance l. |
|
|
Term
|
Definition
p = Ql
Q=sum of point charges
l= distance btwn them |
|
|
Term
|
Definition
consists of two conductors that are close but not touching
fcn:the ability to store electric charge. |
|
|
Term
| When a capacitor is connected to a battery, the charge on its plates is |
|
Definition
proportional to the voltage
on the battery.
(aka the emf of battery) |
|
|
Term
capacitancedoes not depend on
|
|
Definition
|
|
Term
| capacitance (the ability to store electrical charge) is a fcn of |
|
Definition
| the geometry and materials of the capacitor. |
|
|
Term
|
Definition
| is an insulating sheet of material placed bwtn the plates of a capacitor. |
|
|
Term
| T or F: dielectrics do not breakdown, allwing electric flow as readily as air. |
|
Definition
| True, high voltages can be applied without charge passing across the gap. |
|
|
Term
| T or F: dielectrics allows the plates to placed farther apart, thus decreasing the captiance. |
|
Definition
| False, dielectrics allow the plates to be placed together without touching, thus increasing the capactiance. |
|
|
Term
| t or f: if a dielectric is used as an insulator then it can increase the capactiance by a factor K |
|
Definition
| true, K is also known as dielectric constant |
|
|
Term
Concept question: An airfilled capacitor consisting of 2 parallel plates seperated by a distance,d, is connected to a battery of voltage V and acquires a charge, Q.
Question: While is still connected to the battery, a slab of dielectric material with K=3 is inserted btwn the capacitor plates. Will the charge (Q) increase , decrease, or remain the same? |
|
Definition
Increase
recall the capacitor is still connected to the capacitor, so the voltage (V) will continue to be equal to the charge of the battery.
Recall Q= CV
where C is the capactiance , which increase by the use of a dielectric.
Therefore MORE CHARGE (Q) will be pulled from the battery to the plates of the capacitor |
|
|
Term
Suppose the same airfilled capacitor mentioned in the other example, is charged (to Q )and then disconnected from the battery.
Next a dielectric is inserted btwn the plates,
Will Q,C,or V change? |
|
Definition
Q (charge): remains the same
the capacitor is isolated (disconnected) so there is nowhere for the charge to go.
C(capacitance): increases
because dielectric is inserted
V(voltage): decreases
Q= CV
V= Q/C
if the denominator increases while numerator remains the same (aka being divided by even MORE PEOPLE ) the volatge will decrease. |
|
|
Term
|
Definition
| is the maximum field a dielectric can experience without breaking down. |
|
|
Term
| How do molecules in an dielectric arrange themselves? |
|
Definition
The molecules in a dielectric tend to become oriented in a way that reduces the external field.(this is referring to the plates)
aka reduces charge repulsions |
|
|
Term
| why is it important that the molecules in the dielectric materaial reduce repulsions with the respect to the plates? |
|
Definition
electric field within the dielectric is less than it would be in air,
allowing more charge to be stored for the same potential. |
|
|
Term
|
Definition
| as the energy per unit volume & is the same no matter the origin of the electric field |
|
|
Term
| an example of Storage of Electric Energy |
|
Definition
| Heart defibrillators use electric discharge to “jump-start” the heart, and can save lives |
|
|
Term
For capacitors in SERIES
, all capacitors are equal in? |
|
Definition
charge
(each capacitor has to store the same amout of charge). |
|
|
Term
For capacitors in PARALLEL
, all capacitors are equal in? |
|
Definition
|
|
