PHYS208 Fundamentals of Physics II

Answer for Ch. 28, 33E

I worked our the following formulas to make sure of my final values. You more likely worked directly with numerical values since the evaluation would be more staightforward that way.

Switch:
1 2 3 Effective Resistance R.eff (ohm) Current (mA)
 
on off off 2 R1 40.0 3.00
 
off on off  2 R1 + R2 50.0 2.40
 
off  off  on 2 R1 + 2 R2 60.0 2.00
 
off on on (R1 + R2)(3 R1 + R2)

42.0 2.86
      2 R1 + R2    
 
on off on R1(3 R1 + 4 R2)

33.3 3.60
2(R1 + R2)
 
on on off R1(3 R1 + 2 R2)

32.0 3.75
      2 R1 + R2    
 
on on on R1(4 R1^2 + 7 R1 R2 + 2 R2^2)

30.5 3.93
(3 R1 + R2)(R1 + R2)


"http://www.physics.udel.edu/~watson/phys208/exercises/answers/28-33E.html"
Last updated Sept. 13, 1997.
Copyright George Watson, Univ. of Delaware, 1997.