W5D3 POTENTIAL & MORE POTENTIAL

There is still oneunidentified clicker.Whoever this is willnot be receiving any

clicker points.

Let’s Discuss the last Worksheet

Electric Potential

I. Work and Potential Difference

PLEASE TURN IN PART I OF

THE WORKSHEET

Work and Potential Difference

An object travels from point A to point B while two constant forces of equal magnitude, and , are exerted on it. Think about the work done by each force and the net work.

A

B

2F

1F

Is the work done on the object by F1 positive, negative, or zero?

A PositiveB NegativeC ZeroD More information is needed

Work and Potential Difference

An object travels from point A to point B while two constant forces of equal magnitude, and , are exerted on it. Think about the work done by each force and the net work.

A

B

2F

1F

Is the work done on the object by F2 positive, negative, or zero?

A PositiveB NegativeC ZeroD More information is needed

Work and Potential Difference

An object travels from point A to point B while two constant forces of equal magnitude, and , are exerted on it. Think about the work done by each force and the net work.

A

B

2F

1F

Is the work done on the object by the net force positive, negative, or zero?

A PositiveB NegativeC ZeroD More information is needed

Work and Potential Difference

An object travels from point A to point B while two constant forces of equal magnitude, and , are exerted on it. Think about the work done by each force and the net work.

A

B

2F

1F

Is the magnitude of the velocity of the object at point B greater than, less than, or equal to the velocity of the object at point A? Explain how you can tell.

A PositiveB NegativeC ZeroD More information is needed

Work and Potential Difference

An object travels from point A to point B while two constant forces of equal magnitude, and , are exerted on it. Think about the work done by each force and the net work.

A

B

2F

1F

Which, if any, of your responses to questions 1, 2, 3, or 4 would change if the magnitude of F1 was twice as great as the magnitude of F2 ?

Quick Summary If the net force on an object is zero but it is

moving from Point A to Point B, it is in equilibrium and is moving at constant velocity.

If the net force on this object is NOT zero, then it is accelerating and gaining energy (Kinetic).

In the absence of any other forces, the net work done by these forces is equal to the change in kinetic energy + the change in potential energy.

REMEBER: PE=qV UNITS OF V is VOLTS. (Big surprise).

Klick  

Which arrow best represents the electric field at the "x"?

Consider the following:

+Q -Q

Area = A

s=Q/A

UNIFORM ELECTRIC FIELDE

0

E

D

DEFINITION

A Capacitor is a device like the above that STORES CHARGE.There is a potential difference between these two plates. (V)The capacitance C is equal to the charge/potential difference.

C=Q/V Q=CV

Consider the following:

+Q -Q

Area = A

s=Q/A

UNIFORM ELECTRIC FIELDE

0

E

D

Q CV A

AC

V

Work needed to move unit charge from A to B also is (magnitude, anyway) FxD=ED (unit charge)

0

0

0

so

DV ED

AC

V

V DA

CD

So .. What does it all mean??

0ACD

The capacitance of a parallel platecapacitor depends only on geometricalfactors.

NOT on charge or potential difference!

Interesting??Resistors and Inductors Do The Same Thing.

Moving charges in a capacitor while they are in equilibrium

HUH??

Mr. External Ms. Field

WORKSHEETS – Electric Potential

Part II&

thenPart III

&maybe

Part IV or V