AC Signals and Exam 1 Topics

In-Class Activity 1• Given the following oscilloscope display,

express this signal as )2sin()( ftAtv

How NOT to use an oscilloscope

• What’s wrong with this picture? How can I fix it?

• What’s wrong with this picture? How can I fix it?

In-Class Activity 2• What is the current through the resistor if the

voltage source is v(t) = 10sin(100t)?

• What it the power absorbed by the resistor?

+

v(t)

_

In-Class Activity 3• What is the current through the 3kΩ resistor

in the circuit below if the voltage source is vs(t) = 10sin(20t)?

Vs(t)

Exam 1 Information• Date: Thursday October 22, 2009• Time: Regular class time. • What should you bring to the exam:– At least 2 sharpened pencils– Erasers– Calculator (check batteries or bring extra)

• What can’t you bring to the exam:– Any other electronic devices – This means no cell

phones, no mp3 players, no pagers– Any textbooks– Any notes or formula sheets – Every formula you

can have access to will be provided– Any food or drink except bottled water which

must be kept tightly capped when not in use.

Material Coverage1) Supplemental material on units & homogeneity, text

chapters: Introduction through 4, and all the materials covered in class, the labs and homework assignments 1-4. However, the exam will not include the voltage divider method.

2) The test is based on quantitative problems but may also include definitions and explanations of basic electrical concepts, especially from the "Section Reviews," which are found in each chapter.

3) I strongly recommend you visit e-reserve at http://eres.lib.umassd.edu/eres/ 1) Click on Electronic Reserves. 2) Enter EGR 101 in the search box. 3) Enter engineer for the password. 4) Click on the pdf file that is of interest to you.

Review Sessions

• The TA will run a review the week of the exam (time TBD) in the SEC Tutoring room

• I will run an optional review session on the Wednesday before the exam at a time and place TBD. I will email the class when I know

• Neither of us will have anything prepared, we will just answer questions.

FAQ1) Do I have to remember the color codes? NO. You will be given

this information. 2) Do I have to remember English Units? NO. Any English

conversions will be provided if needed. 3) Can I borrow anything from anyone, e.g., a calculator, pencil,

or an eraser? ABSOLUTELY NOT. I recommend you bring extra batteries or a 2nd calculator, more than 1 pencil and a spare eraser.

4) Do I have to know basic geometric relationships like the area of a rectangle, circle, etc.? YES.

5) Do I have to know what a secondary unit is, e.g., Watt (W) in terms of the primary units or other combinations of primary and secondary units? YES, for example, you are expected to know that 1W = 1J/s, and 1 A = 1C/s.

FAQ continued6. Do I have to remember some of the laws that we use so often in

class, e.g., Ohm's law? YES. 7) Do I have to know definitions, e.g., What is current? YES. Look

at the “Key Terms” sections at the end of each chapter and know what the definitions are for each term we’ve covered.

8) Do I bring my own scratch paper? NO, we will provide space for all computations.

9) Can I bring food, soft drink or coffee to the test? ABSOLUTELY NOT. Bottled water is the only thing you can bring and you must keep the cap tightly on it.

10) Am I responsible for chapters other than 1 through 4? NO but you are responsible for the material we covered at the very beginning that is not in the text (see 11).

11) Am I responsible for all the material posted on e-reserve? YES. 12) Am I responsible for all the material covered in labs? YES

FAQ continued13) Will I get in trouble if I am caught looking at someone

else's exam during the test? ABSOLUTELY. You will get a zero on the exam and will be required to sit apart from everyone else for all future exams. Remember: "A student found responsible of academic dishonesty is subject to severe disciplinary action which may include dismissal from the University." For further information please visit http://www.umassd.edu/studenthandbook/academicregs/ethicalstandards.cfm