Recent content by briton

With say arterial anastomosis (eg right and left gastroepiploic arteries) what actually happens at the region where they meet, do to the 2 arteries joining - do you just get a large build up pressure? Is the main reason for having an arterial anastomosis so you have multiple supply to a...

can someone help me understand why decreasing arteriolar resistance will (increase filtration and..) result in oedema? I thought that decreasing resistance decreases pressure so filtration decreases but, all I've got in my notes is that constricting arterioles increases the resistance...

If a ball is thrown in the air and comes momentarily at rest is it at equilibrium? I thought yes because it's stationary, but then again.. there is a resultant gravitational force.. ? Also what is "weightlessness" exactly? Is it when you're in freefall/only gravity acts? so that would be...

Can anyone explain how a reaction force (for example the electrostatc force of the Earth on the stone, and the force of the stone on the earth) works on a molecular level? what is actually happening to *repel (if it does indeed repel??) the object

sorry, I meant the electromagnetic force of the book on the table - this isn't negligible is it? It is of the same magnitude, but in an opposite direction to the force of the table on the book. mm I guess wht I really want to know, is what's happening on the ionic/molecular level... how is the...

pH + pOH = 14

A book on a table. the gravitational force of attraction of the bookon the Earth is negligible... if the reaction force is the electromagnetic force of repulsion of the book on the table, then why is the electromagnetic force of the table on the book negligible??

Thanks, I think I've got it. here I'm trying to work out the mass of the FeSO4 required for a decent titration: mol of Cl2 = 7/(35.5*2) = 0.09859 mol ratio Fe2+ : Cl2 = 2:1 so mol of Fe{2+} which reacts = 0.09859*2 = 0.1972 let total mol of Fe{2+} added to Cl2 = 0.1972 +...

Ok, so using thiosulphate would it be: 2FeS_2O_3 \ + \ Cl_2 \ + \ -> \ 2Fe^{3+} \ + \ 2Cl^- \ + \ 2S_2O_3^{2-} Using this, assuming that I want a titre of MnO4 (concentration say 0.020 mol/dm³) of say 0.015 dm³, then I calculate the mass of FeS_2O_3 to be about 33 grams... have I gone...

Thanks for your reply. I have to follow the stage 1 and stage 2 method (hence reduce the solution of chlorine). I always thought saturation (in this context) was just dissolving? Ie here the chlorine ions are dissolved in water (ie at 7 g per litre)?

Im writing up a plan to find the concentration of saturated aq chlorine - which has been given to me as an approx. concentration of 7 g/dm³. I need to use this value to calculate what suitable quantities of reagents to use. first stage: solution of chlorine is added to an excess of a sutiable...

yeah I'm doing this too (for OCR). I think you measure the pd at the known magnetic field strength, the pd is "Hall pd". and you can use B \ = \ \frac{B_0}{V_0} V where Vo and Bo are what you've just measured. is this correct?

I'm planning an investigation on how magnetic flux density midway between opposite poles of 2 bar magnets varies with separation of the bar magnets (using a Hall Probe). [simply as shown in attachment] To do this, I'll need to calibrate a hall probe (which I think is done by working out the...

F = \frac {1}{4\pi\epsilon_0}\frac{Q_1Q_2}{r^2} E_p = \frac {Q_1Q_2}{4\pi\epsilon_0(r_1+r_2)} E_p = \frac {e^2}{4\pi\epsilon_0(2r_0)} Q = EV \\ Q = eV \\ E_p = \frac {e}{4\pi\epsilon_0(2r_0)} electron volts E_k = \frac{3}{2}kT \gamma \equiv \frac{1}{\sqrt{1 - v^2/c^2}}

cheers! ...