Resistance of a wire with varying cross-section

[requied]

Homework Statement

I know the formulas about resistance of a cylindrical shape copper wire, and applied those on the question but I don't know that whether I am on the right track.

Relevant Equations

R = ρ.L/A

I explained what I want to tell you in the picture I add. Thanks in advance.

 

[etotheipi]

Your formula is a little off, it should be $R = \frac{\rho L}{A}$.

Is your question how to calculate the length of the semicircle?

 

[requied]

Your formula is a little off, it should be $R = \frac{\rho L}{A}$.

Is your question how to calculate the length of the semicircle?

Thank you for correcting I will edit this, I want to write this actually. So, I don't know the second one is a semicircle or not. If that is I did correct. I don't have a question actually, mine is a confirmation.

 

[berkeman]

I don't know the second one is a semicircle or not.

It's not drawn very well, but if they don't say otherwise, it looks close enough to a semicircle to consider it one, IMO.

 

[requied]

It's not drawn very well, but if they don't say otherwise, it looks close enough to a semicircle to consider it one, IMO.

thank you I had also thought so

 

[kuruman]

It's not drawn well at all. A radius of 25 mm is mentioned in the text but a radius of 4500 mm is shown for the supposed cylindrical piece. This figure looks like one that might ask for the magnetic field at the center of the semicircle.

 

[berkeman]

It's not drawn well at all. A radius of 25 mm is mentioned in the text but a radius of 4500 mm is shown for the supposed cylindrical piece.

I think the "25mm" is the radius of the wire itself, not the radius of the semicircle portion of the wire form. Yeah, that confused me pretty well also.

 

[kuruman]

I think the "25mm" is the radius of the wire itself, not the radius of the semicircle portion of the wire form. Yeah, that confused me pretty well also.

Ah, yes!

 

[requied]

I think the "25mm" is the radius of the wire itself, not the radius of the semicircle portion of the wire form. Yeah, that confused me pretty well also.

My native language is not English. See it from my angle