Answers for Assignment 8

41. Proof by contradiction.


42. (a) The force on the left wire points left, that on the right wire points right, and both have magnitude

                                       
     mu0             a+b  
F = ----- I1 I2  ln (---)              
     2 pi             a
(the two forces cancelling)

Fbot= [mu0 / (2 pi)] I1 I2 L / (a+b)       down

Ftop= [mu0 / (2 pi)] I1 I2 L / a              up

Fnet= [mu0 / (2 pi)] I1 I2 L b / [a (a + b)]   up

43. Proof.

44. Proof

45. Proof


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Last revised 1998/04/17