# Recent content by demode

1. ### Speed of Sound

I just completed a lab in which we created standing waves in a fixed length of pipe using a function generator. An oscilloscope was used to measure the amplitude of the waves. The frequency was changed until a resonant condition was met, and then the location of all the nodes/antinodes was...
2. ### Chemistry behind airbag deployment. How to demonstrate?

Thank you very much for the quick replies! They were very helpful
3. ### Chemistry behind airbag deployment. How to demonstrate?

Thanks so much for the quick reply jpr0, but yeah I was looking more so at the chemical reactions that actually drive airbags to deploy and whatnot.. Thanks anyways though!
4. ### Chemistry behind airbag deployment. How to demonstrate?

Hey there everyone! For my chemistry class, I had to write a feature article about the chemistry behind airbags (pretty fascinating stuff), and now my teacher has dropped the bomb that we must do a presentation that explains what we studied.. I was hoping to do a small (and i mean small)...
5. ### Distillation Lab Question!

Hey everybody, I just completed a small distillation lab for my high school chemistry class. We took a sucrose/water solution, added yeast to ferment it, and distilled it into ethanol for about an hour in the lab. I'm trying to write my lab report, and I've hit a huge stumbling block! One of...
6. ### Sound Wave Problem

Can anyone give me some insight?
7. ### Sound Wave Problem

1. A soldier hears the sound of the firing of a distant cannon 6.00 seconds after seeing the flash. If the temperature is 20 degrees Celsius, how far is the soldier from the flash? 2. D = R * T 3. Since the speed of sound at 0 degrees Celsius is 330 m/s, the speed of sound at 20...
8. ### Resistors in Parallel!

1. Ten 110-ohm lamps are connected in parallel to a 110-V house line. A) What is the combined resistance of the ten lamps? B) What current flows in the line when all ten lamps are operating? C) What power is then being supplied to the circuit by the line? I just wanted to have someone check...
9. ### Difference in Potential

D'oh.. I should have thought of that. Would I use that formula for EACH resistor, or could I use it once using the Total resistance? **EDIT** Retract that, using the total resistance would give me the same result if I just added together the two differences of potential I'm solving for.
10. ### Difference in Potential

Thanks so much for your help.. It seems I have one more queston.. If you know the resistance of two resistors (connected in series) as well as the current flowing through them, how do you find the difference of potential across each resistor?
11. ### Difference in Potential

Ok, I'm only unsure for parts B and C, because I didn't know whether to use the difference of potential solved in part A for parts b and c.
12. ### Difference in Potential

1. Five similar lamps are connected in series to a source providing a difference of potential of 550 V. A) What is the difference of potential across each lamp? B) If the current flowing in the circuit is 1.10 A, what is the resistance of each lamp? C) What is the resistance of all five lamps...
13. ### Equipotential Lines and field mapping

Equipotential Lines!!! I recently did a lab in class that dealt with electric field mapping (very similar to http://physics.nku.edu/GeneralLab/211%20Elect%20Pot.%20&%20Field%20Map.html) and i have to write a lab report now.. I don't understand why the equipotential lines are always...
14. ### Two heat/temperature problems

1. How many celsius degrees does the temperature of a mass of 1.00 kg of water fall for each 83.8 kJ of heat it loses. 2. Not so sure about EQUATIONS but I have my own way of going at it. 3. 83.8 kJ / 4.19 J * (1.00 kg * 1000) = 0.2 degrees celsius 1. How much heat is required to...
15. ### Centripetal force question + other question

1. A dog sits 1.50 meters from the center of a merry-go-round with an angular speed of 1.20 rad/s. If the magnitude of the force that maintains the dog's circular motion is 40.0 N, what is the dog's mass? 2. Fc = (mv^2) / r 3. We were provided with the answer "18.5" but I do NOT...