Recent content by coolnufc

The beam current in a television tube is 32mA. The electrons travel at a speed of 4.2x10^7m/s through a distance 21cm. a) The number of electrons striking the screen in 1 hour is? I did: Q=IT = 0.032A x (60x60)s = 115.2 C Number of electrons = 115.2/1.6x10^-19 = 7.2x10^20 b) The...

It was nichrome wire (28 swg) i was using if that helps

Hi guys, I am trying to work out ρ in an experiment. Ive got down to ρ/AxV = 6.4 I know V = 2 and A=0.0907mm, but it should be m. If i then work it out i get a stupidly small answer. Anyone help me out. Its like 0.0016096

Hi, sorry to bug you, but i am currently doing my courseowrk too, and my teacher told me to do mine on resistivity, but not sure how to conduct the experiment. Should i be measuring the voltage and current, and working out the resistance, to then determine the resistivity? How do you do it?

I am going to be doing this experiment, and changing the length. So would i be measuring the voltage and current, then working out the resistance. And from that work out the resistivity of the wire? Would this be ok?

Hi guys, I am currently in my AS year and a piece of coursework on resistivity of metals, how you derive the equation. But for the coursework i have to write an abstract on it, linking my experiment to a case study, does anyone have any good websites or information to help me out. This is...

Could anyone help me with this, i have an answer but I am sure its not right. Bleach is an aqueous solution of sodium chloride and sodium chlorate(l), NaClO, in a 1:1 ratio. It is produced by dissolving chlorine gas in cold dilute aqueous sodium hydroxide. a) write a balanced equation for...

Thank you so much, you have been a massive help. I think i understand it a lot more and i will check that website out. I was used examstutor because our school signed us up to it. Do you have any ideas about this? a ) How would the resistance of a piece of wire change if i) the length...

No i haven't been taught it. I found something on a website about it. So i just use the p.d the questions gave me. 14 volts? So 14/7 = 2A?

7? wild guess.

So to work out the current i need the p.d and the resistance. I know the resistance of PQ is 5? I just need to work out the p.d?

Im not sure how to do it because one is in series and one is in parallel.

well on part a. i did 3 x 6 / 3 + 6. so i tried that for part b. by doing 3 x 6 x 5 / 3 + 6 + 5 = 6.43. and then i did 1 / (1/6 + 1/5 + 1/3) = 1.43.

Umm, well i came out with two answers. :S I got 1.43. and then i tried another way and got 6.43.

yeah i do. but I am still confused with the other questions. why is 14V not across PQ as well as the whole thing, it hasnt split into parallel yet?