
#1
Jun1012, 06:27 AM

P: 12

Is it correct that the charge of an electron in Coulombs is
 1,602 176 565(35) • 10^{19} C ? By inserting this in the formular for current I = Q / t, that would make the current a negative number. I dont reckon having read about negative currents though. So what's the explaination for how the negative sign dissappears and currents end up always being positive? 



#2
Jun1012, 06:56 AM

Mentor
P: 40,876





#3
Jun1012, 07:03 AM

P: 12

but is it correct that the charge of an electron in Coulombs is  1,602 176 565(35) • 10^19 ?




#5
Jun1012, 07:18 AM

P: 12

so lets say.. 18 C would be then be 18 / ( 1,602 176 565(35) • 10^(19)) electrons? That's a negative number, how is it possible to have a negative number of electons?




#6
Jun1012, 07:20 AM

Mentor
P: 40,876

What problem are you trying to solve? 



#7
Jun1012, 07:33 AM

P: 12

In the text book that I have, it comes with this example:
A 5 amp current flows for an hour. The total charge that passes by in such case, is Q = I • t = 5 A • 3600 s = 18000 C or 18000 Coulombs. Now how many electrons is that? 



#8
Jun1012, 07:35 AM

Mentor
P: 40,876





#9
Jun1012, 08:09 AM

P: 12

So coulomb is not the unit for charge, but the unit for the magnitude of charge?



Register to reply 
Related Discussions  
How many coulombs of positive charge are in 1.91 mol of O2 gas?  Introductory Physics Homework  1  
coulombs law, vectors and chargeHELP!  Introductory Physics Homework  1  
Coulombs Law...find q (charge)  Introductory Physics Homework  1  
Coulombs Law with one unknown charge  Introductory Physics Homework  6  
Electric Charge, Coulombs law  Introductory Physics Homework  4 