Reading Quiz 2. What is the SI unit of capacitance? Capaciton Faraday Hertz Henry Exciton What quantity is represented by the symbol ? Electronic potential Excitation potential EMF Electric stopping power Exosphericity Answer: C

is always perpendicular to an equipotential surface. 3. The electric field is always perpendicular to an equipotential surface. is always tangent to an equipotential surface. always bisects an equipotential surface. makes an angle to an equipotential surface that depends on the amount of charge. 4. This chapter investigated parallel capacitors perpendicular capacitors series capacitors. Both a and b. Both a and c. Answer: E

What quantity is represented by the symbol ? Electronic potential Excitation potential EMF Electric stopping power Exosphericity

What is the SI unit of capacitance? Capaciton Faraday Hertz Henry Exciton

The electric field is always perpendicular to an equipotential surface. is always tangent to an equipotential surface. always bisects an equipotential surface. makes an angle to an equipotential surface that depends on the amount of charge.

This chapter investigated parallel capacitors perpendicular capacitors series capacitors. Both a and b. Both a and c.

Finding the Potential from the Electric Field The potential difference between two points in space is where s is the position along a line from point i to point f. That is, we can find the potential difference between two points if we know the electric field. We can think of an integral as an area under a curve. Thus a graphical interpretation of the equation above is

EXAMPLE 30.2 The potential of a parallel-plate capacitor

EXAMPLE 30.2 The potential of a parallel-plate capacitor

EXAMPLE 30.2 The potential of a parallel-plate capacitor

Finding the Electric Field from the Potential In terms of the potential, the component of the electric field in the s-direction is Now we have reversed Equation 30.3 and have a way to find the electric field from the potential.

EXAMPLE 30.4 Finding E from the slope of V QUESTION:

EXAMPLE 30.4 Finding E from the slope of V

Exam 1 Review Chapters 26 – 30 Up to and including section 30.4 The exam won’t cover sections 30.5 to the end of the chapter The exam will cover Field lines and surfaces of equipotential for different charge configurations Force and Electric Field of point charges Potential and Potential Energy of point charges Using Gauss’ Law to determine something about field or charge

Group Problems Start Ch 29 HW Chapter 30 HW may be on exam (topics up to and including those covered in Sections 30.1 – 30.4)