What is Lab: Definition and 1000 Discussions

this lab is very similar to mine basically i can only seem to derive a portion of the formula, I=mgb/al - mb^2 where b- radius, g-gravity, al- angular acceleration. I do not get the right answer: here is what i did do however, Fnet=ma T-mg=-ma (acceleration is downwards) so T=(mg-ma) so then...

Homework Statement These questions are based on a laboratory measuring electric field in a two-dimensional deionized water tray using a 12 volt potential difference from a power supply. The positive electrode is on the right-hand side of the tray and the negative electrode is on the left...

I have a lab and I'm having a hard time calculating or even understanding how to calculate the uncertainty. It wants me to calculate the uncertainty of temperature. Here is my data: time (mins) Temp (°C) 2 23.2 4 26 6 29 8 31.5 10 33.5 12 35.5 14 37.6 16 39.7 18 41.8 20 43.9 Don't I need some...

Hi all. We're moving to a new lab and I need to have a reliable ground for ESD protection, e.g. connecting the ESD mat safely. My questions are: can I just use the ground in the power outlet, or I need to request a different ground? Do I need to connect a resistor between the mat and the ground?

Attach the best pictures of the lab you work in here! Theoreticians can attach pictures of their powerful pc's! My Laser Lab: http://img2.freeimagehosting.net/uploads/5e71c5fd82.jpg

Bacteria Make Major Evolutionary Shift in the Lab This is pretty cool.

Why is it conventional to analyse compton scattering in the lab frame (fixed target) whereas all other processes I've seen are analysed in the center of momentum (colliding beam) frame. Are there any experiments where one would collide electrons with stationary muons e.g.?

I work with acetylacetone in my lab. The MSDS, in the Health Hazard section, lists the target organ as the thymus. I don't think I've ever seen the thymus listed in any MSDS as a target organ. Usually, it's the liver, or the central nervous system. I looked into what the thymus does, and...

Homework Statement I have a problem while writing the uncertainty of datas in my lab report (portfolio). So, here is my question: While multiplying some data with different uncertainties, I do multiply their uncertainties too, right? Then, if the multiplication of uncertainities has...

You find two unlabelled diffraction gratings in your lab. From purchase records, you know that one grating has 5000 lines/cm, while the other has 10 000 lines/cm. Given the following equipment, describe how you would determine which is the grating with 10 000 lines/cm: • Red laser • detection...

Centripital Force Lab - PLEASE HELP! Homework Statement Ok so i need to do this lab, write a report, and prepare a defence for tomorrow pretty much i spin a mass horizontally on a string attached vertically to a force sensor. i hold onto a plastic tube through which the string goes and...

For our physics lab we hung a mass attached to spring above a motion detector. First we took some data with the spring at rest. Using this data, we determined our zo value. Then we set the spring in motion and took data. Using position, velocity, and time data, we calculated K, U, & K+U =...

Physics Lab Question-- any ideas? For our physics lab hung a mass attached to spring above a motion detector. First we took some data with the spring at rest. Using this data, we determined our zo value. Then we set the spring in motion and took data. Using position, velocity, and time...

last part! hi QUESTION There are two standard methods for the solar energy to be trapped and used domestically. One is to use solar cells, which convert the radiation energy to electrical energy. The other is to use a solar panel, which absorbs the solar radiation to heat water. You...

Homework Statement How much frictional torque is there? I know angular acceleration and torque applied. (I do not know if this can be used to find torque friction, though.) Homework Equations The Attempt at a Solution I know that Frictional torque can be found by doing Torque...

Maybe someone can help explain this a little for me. In my lab reports, I am to show qualification of error and then quantify one of those values. Obviously, in some of hte labs, only certain causes of error can be reasonable shown. For example, on the angular velocity lab, I can say that the...

Hello! I am a high school teacher and I am doing a lab on Newton's laws. I need help interpreting part of the lab because the results did not come out to what the laws would have predicted. The lab consisted of setting up two carts, one with a spring which can be compressed and one...

is there a standard font I should use? If there isn't, what font do you use?

Homework Statement Some students had a disagreement about the esterification reaction between ethanol and ethanoic acid. Student A feels that the -OH group from the acid combines with the H from the alcohol functional group. Suggest a hypothesis for his feeling and design a lab to test the...

Does anyone know why fluoride ions inhibit fermentation and why cyanide ions have no effect on fermentation?

I'm studying for a lab exam tomorrow and I just want to make sure of some things. One of the experiments was on the effect of inhibitors on enzyme activity. We were studying the reaction 2 H2O2 (hydrogen peroxide) --> 2 H2O + O2. This reaction uses the enzyme peroxidase. Hydroxylamine...

I'm studying for a lab exam tomorrow and I just want to make sure of some things. One of the experiments was on the effect of inhibitors on enzyme activity. We were studying the reaction 2 H2O2 (hydrogen peroxide) --> 2 H2O + O2. This reaction uses the enzyme peroxidase. Hydroxylamine...

So, in the lab that my class just finished for angular momentum, we had a rotaring hollow cylinder rotating and we had to drop an iron disk square on top of it to measure the momentum before and after to verify conservation. The professor inquired how the result would be affected if we had...

A metal disc is placed in a uniform magnetic field of flux density,B,acting through the plane of the disc at and angle,\theta.When the dis is rotated an e.m.f. is induced between the centre and the rim of the disc. http://img158.imageshack.us/my.php?image=scanlc2.jpg Design an experiment...

Everyone in my office (8.5 x 3.5 x 6 meters) was complaining of dry eyes/throat. We thought "hey we should check the humidity". We bought two separate humidistat's that both read 15% RH at 73 degrees F! So we bought a humidifier. Just one of the small ones that holds 2.2 gallons and empties...

Homework Statement A sol;n of 14.05 mL of NaOH is mixed with 50.0 mL of 0.2102 M H2SO4 (standardized) and allowed to react. The sol'n (H2SO4 and NaOH) is still acidic, so it is titrated with 10.55mL of standardized KOH (0.08883M) until the equilivance point is reached. What was the...

The vapor presurre of mercury is 0.00185 mmhg at 25 degree C. A single drop of Hg(0.1 mL) is spilled in a laboratory of dimensions 10m x 10m x3m. Does the entire drop evaporate? What is the partial pressure of Hg in the laboratory? (Use 13.6 g/ml for the density of Hg.) (b) The normal boiling...

Which Lorentz transformation takes the lab system to the CM system? Lab system: p_a = (E^{lab}_a, \vec{p}_a) and p_b = (m_b, \vec{0}) CM system: p_a = (E^{CM}_a, \vec{p}) and p_b = (E^{CM}_b, -\vec{p}) For a binary reaction a+b->c+d, the textbooks I have say quite a lot about the...

[SOLVED] Biology Lab Abstract: Photosynthesis Homework Statement I am having trouble understanding how increased transmission is an indication to photosynthesis occurring. My teacher gave us the prediction for this lab: if photosynthesis is happening then transmittance goes up. I know...

Homework Statement So basically we allowed a cart to role down an incline plane and we recorded the results with a ticker taper. Now there are a couple of questions that my teacher asked that I do not fully understand. This entire section is a bit shady. I do not fully understand what...

We did a lab, where a cart was rolled down a ramp and a tickertape was attached to the cart as it rolled down. When the cart finished the course of rolling down, a line was drawn across the tape through every sixth dot to show that it is an interval of 0.10s. Then we had to make 3 graphs...

Graphs Of Acceleration And Force Hi! We did this lab...on Newton's Second Law. we are trying to prove the formula F=ma... Now i drew this graph of acceleration vs time and force vs time...they look similar..how can i interpretate them? someone help! MY lab is due tomorrow!

In a physics lab, a small cube slides down a frictionless incline as shown, and collides at the bottom (where it is now moving horizontally) with a cube that is only one-half its mass. If the incline is 30 CM high and the table is 90 CM off the floor. where does each cube land? the teacher...

Could someone please provide some assistance as to how to approach this problem. I am doing a thermochemistry lab: The second Virial coefficient of CO2 and I am not sure how to approach this problem. Just a few hints would really be appreciated. I have tried differentiation, integrals no luck...

Homework Statement How would you prepare a 500 ml lab stock of 20% (w/v) SDS That is all that is stated in the problem. Homework Equations I'm assuming for w/v the volume would be 0.5L but the weight I'm not sure. The Attempt at a Solution 0.5L x .20 = .1g SDS / .5 L .. is...

Hi there. I'm having issues with a high school lab that deals with acceleration of objects down inclined planes. At the top of my lab questions, there's a simple diagram (just a triangle with a rectangle on the hypotenuse, representing a cart), and one of the questions pertains to it: What is...

I was looking up möbius strips online, and naturally wandered into klein bottle territory, and ended up at http://www.kleinbottle.com/" . It's reading week, and I'm in the university's computer lab. Heaven protect me if an overworked English Major comes over and asks why I'm disturbing the...

I have decided to do a a cyanotype experiment for my chemistry investiagtory project, this year in school. To do that, I need Ammonium Ferric Citrate, which my school lab does not stock. Also, local retailers don't have it. How can i prepare ammonium ferric citrate in my laboratory using...

Homework Statement Explain what happened when the solution was added to water in terms of Le Chatelier's principle and ocument your explanation using observations. Think Carefully! write out the correct mass action expression before you answer--this is subtle! Homework Equations a...

Well I have this lab on electric field lab and what I did was measure the voltage from different distances on a parallel plate. So when I plotted the graph Voltae vs. Distance, I got a linear line and the equation was y = 85x (somewhat like that disregarding the y-intercept). My concern is what...

I work at a start company that is looking to separate the isomers of one of the compounds. any suggestions of good labs that can do this work? thanks for your help! isa

Homework Statement in practice is is assumed well insulated heat exchangers are adiabatic. With reference to this heat exchanger, carry out the necessary calculations and then give an opinion as to the validity of this assumption. Homework Equations Observation Thotin 55.88, Thotmid...

In this potentiometry lab, serial dilutions were made from stock 0.1M solution of NaF that ranged from 1E-2M to 1E-6M. Then these solutions were measured with a fluoride ion-selective electrode for response. The question is why does the potential become constant when the concentration of NaF is...

Analysis: What are the effects of various temperature, pH, alcohol, and saline solution treatments on peroxidase activity? What are the optional ranges of temperature and pH for peroxidase? Are alcohol and saline solution inhibitors or activators? Sate the dependent, independent and...

I have this practical problem in my laboratory and would like to see it formulated in a formal calculus way, but my math skills were never very high and they are very rusted now and do not know how to formulate (much less solve) the problem. A biological sample containing a virus is run...

Here is the problem I am having: Professor told me to find the spring constant using our slope of the graph. Now the graph that I did on the excel went something like this: On the X-axis of the graph was the weight of the hanging mass in Newtons and on the Y-axis of the graph was the...

Rub a balloon containing a few pieces of Styrofoam towards your sweater or a piece of wool/fur. What do you observe when you touch with your finger one of the piece through the balloon? Why does this happen? The Styrofoam repels within the balloon. You charge the balloon negative by rubbing...

Homework Statement Figure out the total distance traveled by a ball bouncing vertically when its dropped from a height of 6 ft above the ground and the time the ball was in motion for. G 32ft/s^2 ball one dropped from 72 inches bounced back up 53 inches with a Coefficient of...

A student takes 0.45kg of ice. The ice is initally at -23'C. She heats the sample in an oven until the temp is 134'C. a). What is the NRG needed to heat the ice to its melting point? b). What is the NRG needed to change the solid ice into liquid water? c). What is the NRG needed to heat the...

I think I calibrated my pH meter improperly during lab; I got a pH of 4.70, which doesn't make any sense, as KI isn't acidic, as far as I know. After electrolysis (2I- + 2H2O --> I2 + 2OH- + H2) with a 9V battery, I found a pH of 9.97, which doesn't seem to be correct, either: (change in...