Equations & Calculations
What is the equation for density?
D=m/v
How many sigfigs are in:
25
2
Why is it incorrect to say human error when accounting for discrepancies in your measurements?
What is the difference between an open and a closed system?
Conservation of mass and energy in a closed system, energy flow is free in an open system
Give the equation for SLOPE:
the change in y over the change in x
What is the 3-step method?
eq in words and/or variables
substitute in data
determine answers in sig figs and units
How many sigfigs are in:
12.46
4
The _____ of a measurement describes how close the measurements comes to the true value. The _____ of a measurement depends on its reproducibility.
Accuracy; Precision
What is the 5% rule?
If the y-intercept is less than 5% of your greatest y value, it is negligible and can be discounted (counted as zero).
Where did Ms. Weber graduate from and BONUS +10 points if you can name her undergraduate degree.
Oregon State University (Go beavs!!) Biomedical Sciences
If you are going 100 km/hr, what is your speed in meters per second?
27.7 m/s
BONUS 50 POINTS IF ANSWER WAS GIVEN IN CORRECT NUMBER OF SIGFIGS= 30 m/s
When are zeros significant?
When they are between non-zero values or are trailing after the decimal point.
When you are measuring a liquid, what is the name of the true "line" you measure from?
Miniscus
What is the equation for percent error?
What is the order of sections in which we write our lab write-ups?
Intro
Materials
Procedure
Data
Results
(Discussion)
Conclusion
Convert 1500 meters to miles
(5280 ft=1 mile)(1 meter= 39.37 inches)
0.93 miles
How many sigfigs are in:
70.890
5
What is the equation for circumference?
2pi*r
Which object would probably require a larger number of significant figures to accurately measure: The length of dog's tail or the length of a human chromosome? WHY?
The following sentence was in a lab write-up turned into Mr. Buchli for grading. What is wrong with this sentence? (There are 3 things).
"I measured the beaker and wrote it on my paper then I told my partner to write in on her paper and we calculated our volume from the beaker".
1. use of I (personal language).
2. Vague, not detailed at all
3. Run-on, incorrect grammar.
How many ng are in 5.27*10-2 kg?
5.27*1010 ng
How many sigfigs are in:
0.0056700000
8
Find the radius of a beaker if the volume is given as 500 ml and the height is 30 cm.
2.3 cm--> 2 cm
You're given a sample of plutonium to power a battery that will provide sustainable energy to the entire planet. However, the battery will ONLY TAKE PURE SAMPLES of plutonium, or else it will not work.
You mass the sample and find that the sample's mass is 1001 g. You then put the sample in a beaker of water and find that it displaces about 47 ml. If the accepted density of plutonium is 19.36 g/cm^3, can you accept this sample to save the world's energy crisis and WHY
no:( 21.27 does not equal 19.36
When can we take our goggles off DURING A LAB and why did we wear goggles for our Density of gas activity even though we were only working with Alkaseltzer?
When Ms. Weber or Mr. Buchli come around and collect all the waste containers; when everyone is finished with their lab work; We wore goggles because its important to facilitate good habits, SAFETY, and procedure in the lab.