In: Physics
Each of two identical uniform metal bars has a resistance R.
The end of one bar is welded to the end of the other bar (Figure 1) . In terms of R, what is the resistance of this combination?
What is the resistance if the bars are welded together along their length? (Figure 2)
R = rho * L/A
If the end of one bar is welded to the end of the other
bar,its length doubles.
Doubling the length will double the R.
so new resistance will be 2R
If the bars are welded together along their length, it
area doubles. Doubling the area causes resisatnec to be
halved.
So new resistance will be R/2