Homework
(see bottom of page for chapter summaries)
Answers
for homework problems are entered using Blackboard. You can get there using
this link:
All of
the homework problems have been entered into Blackboard. Therefore, be sure to
answer the questions as asked online – they will have different numbers
each time.
For the
first assignment, you will have as many attempts as you like to enter answers.
This should allow you to get practice using the system. For subsequent
assignments you will have two attempts.
If you
have errors in your first submission and want to use your second attempt, you
will have to rework all of the problems in the assignment. This is an awkward
feature of Blackboard – we donÕt have control over it.
Ask
your TA if you have further questions.
Helpful hints for Blackboard Assessments
Submitting Answers For answers requiring computation,
(not multiple choice)
á
Rounding: Blackboard allows a 1% error above or below the
correct solution, so if you do round only round to 3 significant figures.
o
Example:
|
Correct answer |
Solution window |
Wrong submissions |
Right submissions |
|
195.4 |
193.446 –
197.354 |
190, 193, 198,
200É |
195.4, 195, 193.5,
197.3É |
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Large or
Small numbers: Symbols
like *, ^, or X , x donÕt
mean anything to Blackboard. If you want to use abbreviated notation use the
letter e (it stands for
exponential notation e ≡ x 10 ^ )
o
Example:
(capitalizing and spacing doesnÕt matter here)
|
Correct answers |
Wrong submissions |
Right submissions |
|
2,340,000,000 |
2.34 x 10^ 9
, 2.34 * 10^9, 2.34 X 10
^9 |
2.34 e 9 , 2.34E9 2.34e 9 , 2.34 E9 2340000000 |
|
0.0000000567 |
5.67x10^-8,
5.67*10^-8, 5.67X10^-8 |
5.67e-8, 5.67 E -8 5.67 e-8, 5.67E -8 .0000000567 |
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Signs: If asked
for a sign put it in as a minus sign (-).
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Example: the charge of an electron.
|
Correct answer |
Wrong submission |
Right submissions |
|
-1.6 e -19 |
1.6 e -19 |
-1.6 e-19, -.00000000000000000016 |
UNITS for Answers For most answers there is also a box for submitting
units.
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Standard
abbreviated notation: When
asked for units standard abbreviations are used in all cases. Here is a table of examples of common
units. (CASES
ARE IMPORTANT)
|
Property |
Unit |
|
Property |
Unit |
|
Property |
Unit |
|
Mass |
kg |
|
Energy |
J |
|
Electric Field |
N/C or V/m (ch. 19) |
|
Distance |
m |
|
Resistance |
Ohms |
|
Magnetic Field |
T |
|
Time |
s |
|
Current |
A |
|
Linear Density |
kg/m |
|
Velocity |
m/s |
|
Charge |
C |
|
Electric Flux |
Nm^2/C |
|
Force |
N |
|
Work |
J |
|
Intensity |
W/m^2 |
|
Power |
W |
|
Frequency |
Hz |
|
Angle |
Degrees |
|
|
|
|
|
|
|
Electric potential Potential
difference |
V |
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Exceptions:
o
Greek
letters: Example ½
(omega), represents Ohms, correct answer is ÔOhmsÕ.
o
Other symbols: Example o (degrees), represents an angle
in degrees, answer
ÔdegreesÕ.
o
Special cases: These (and usually the ones above) will be noted in
each problem.
¤
Example: What is
the wavelength of this laser? (Please give answer in ÔnmÕ). Correct answer is nm.
¤
Example: What is
the energy associated with a bound electron? (Please give answer in ÔeVÕ). Correct answer is eV.