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    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...
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    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)...
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    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...
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    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...
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    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...
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    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...
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    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...
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    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...
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    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...
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    Could you calculate the mass of the planet?

    1. If you know the distance to a planet and the centripetal force on it, could you calculate the mass of the planet? Explain. Fc = (MV^2) / (R) I don't even know where to start; in the equation above, you can only substitute the known centripetal force in, but you can't substitute the...
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    Two simple questions

    First Question 'A worker is rolling a 480-N barrel up a 16-m ramp onto a platform 2.0 m above the floor. The efficiency = arrangement is 40%. What is the work output, work input, and effort applied to the barrel.. To find work output, you would just multiply the resistance force (480) by...
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    Another Law of Work queston

    The prompt: "A 20-kilowatt motor operates an elevator weighing 10,000 N. What is the maximum speed at which the motor can raise the elevator?" How can i solve for speed? I know that power = work / time, and work = force * distance, but I cannot solve for work because I only know a force...
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    Question involving LAWS OF WORK

    I have been given the prompt: "Using a set of pulleys, a mover raises a 1000-N crate a distance of 5.00 m. This is accomplished by pulling in 20.0 m of cord" I need to find How much effort would have to be applied if this were an ideal machine If the effort actually applied is 300...
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    Demode cant simplify equations =(

    I was given the problem: "What minimum force is required to drag a carton of books across the floor if the force is applied at an angle of 45 degrees to the horizontal? Take the mass of the carton as 40 kg and the coefficient of friction as 0.60. Free Body Diagram (Given by physics teacher)...
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    Awesome Sony commercial!

    http://www.bravia-advert.com/paint/thead/ [Broken] Sony's new line of commercials for this new television is absolutely amazing.. Check them out!
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    Coefficient of Friction problem!

    The question states: "What is the coefficient of friction between a sled and a plane inclined at 30 degrees from the horizontal if the sled just slides without accelerating when given an initial push?" I have drawn a free-body diagram and labeled all of the forces (I think i labeled all of...
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