# Search results

Homework Statement Hi, I did a lab experiment where I took a 5L vessel made of some material that isolates gas inside and thus behaves like an isolated system (adiabatic). I then pumped gas from ~90kPa to up to 150 kPa... recorded the temperature, then let the gas 'expand' by opening the...
2. ### Gel filtration chromatography

Hi, I am studying for my biochemistry lab exam. While going over one of the questions... I came across one that I can't answer...help will be appreciated. Question under analysis is related to a previous question. (Previous question) A gel filtration (size exlcusion) is set up and the...
3. ### Momentum operator

This is not really a homework problem but rather a homework-related question.. When I came across my homework (and my textbook: Atkin's physical chemistry 9th Ed.), they defined the momentum operator as: p_x = - ( \hbar / i ) * d/dx... but i have seen in other sources that they define it...
4. ### Can anyone help me make sense of my lab results?

Hello, I recently did an experiment of nanoparticles (specifically Au Nanoparticles) We did the Turkievich method and the borohydride method) for the turkievich method we got good results and this is indicated by the UV spectrum of the sample.. for borohydride though... we got a...
5. ### Selectivity of free radicals in halogenation.

Hi, can anyone please explain what selectivity of free radicals is? For example, there is an MCAT question that I recently came across and that can't seem to make sense of the answer. Which of the following halogens will give the greatest percent yield of tertiary alkyl halide when reacted...
6. ### Interference - two wave source

I do not know how to approach this. I am trying to use r1 - r2 = mλ but I cant seem to find the answer! please help. I figured it out that it is constructive, but i just dont know how to mathematically prove it. r1 - r2 = mλ.
7. ### AC circuits.

Hi, so I have a homework problem and I don't know how to approach. I am given a circuit, with an AC source, a resistor ( 2 Ω) and a unknown circuit element (that could be an inductor or a capacitor). I am also given a graph with the Voltage amplitud across the AC source (Which happens to be...
8. ### R-L Circuit, Finding the current through a circuit element.

Homework Statement So I am having a hard time trying figuring this out. The question asks for the current through the 20Ω resistor as well as the current through the battery AFTER THE SWITCH HAS BEEN CLOSE FOR ALONG TIME. Here is a picture of the circuit. http://i.imgur.com/VjoFSUd.jpg...
9. ### Moving Square Loop through a Magnetic Field

Homework Statement A square loop of side 1.5m and Resistance 2Ω is pulled with a constant velocity v=0.3m/s through a smaller region with a constant magnetic field B (out of the page) of 4T. The figure shows the position at t=0. Calculate the magnetic flux of the coil at t=4s.. Here is a...
10. ### Z Distribution for lightbulls

So, I have been studying for my chemistry quiz and I came across a problem that I can't really get, or rather, part of the solution. The problem itself is easy, it's just the way my teacher solved what confuses me. Here it is and thanks in advance. There was an histogram for lightbulbs...
11. ### Rotation of a Rigid Body

Homework Statement The two blocks in the figure are connected by a massless rope that passes over a pulley. The pulley is 14cm in diameter and has a mass of 2.4 kg. As the pulley turns, friction at the axle exerts a torque of magnitude 0.54 Nm . Homework Equations so m1 = 4.0kg m2= 2.0 kg M...
12. ### Kinetic and Rotational energy of a sphere

Hi guys so this is my first time posting a question on this amazing forum, i hope i am doing this right since i read that no one will help me if i am missing something. Anyways, i am dealing with a physics problem that it driving me crazy (mainly because my teacher does not explain anything!)...