PDA

View Full Version : Resistance again


Roary
Feb21-04, 07:58 PM
Not an actual problem, but I'm not sure how to figure these out.

I am given the mass of a sample of aluminum. (Let's say it's 112g or something) I am given a shape: cylindrical tube, with the conditions that the diameter of the circular face = the height. (Also given, density of aluminum, a chart with the resistivity values, at standard temp of 20C). How on earth would I find the resistance between the top and the bottom face of the shape?

Roary
Feb22-04, 09:49 PM
R = pl/A (Resistance = resistivity * length/area) is probably the equation to use. But I have no length? The mass given, and density can find the length somehow? (I would use area of a circle only correct?)

dlgoff
Feb23-04, 02:08 PM
Is the shape a "cylindrical tube" or just a cylinder?

Since you haven't given a tube wall thickness I'm assuming you mean a cylinder.

But I have no length?
But you said,
diameter of the circular face = the height