Problem 20.45 A long, straight wire carries a current I, and produces a magnetic field Be at a distance re from the wire's center. Part A In terms of Bo, determine the magnetic-field strength at a distance To/2 from the wire's center. Express your answer in terms of Bo. ΑΣΦ B' = Submit Part B B' = Submit 3 In terms of B₁, determine the magnetic-field strength at a distance 3r, after the current is increased to 610 Express your answer in terms of Bo VT ΑΣΦ 3 Provide Feedback Request Answer ⒸIR ? Request Answer (3 ?

e. Draw the Amperian loop that will allow you to find the magnetic field at a point P inside the cylinder (r < b). f. Write the integral B ds = $ B cos o ds in terms of the unknown B and the givens 7 and/or b. Your answer should look familiar. g. i. What is the current Ithru going through your Amperian loop? Hint: the current is spread out evenly over the cross-sectional area of the wire so set up a ratio of areas. Check that your expression for Ithrough has the dimensions of current. h. Use (f) and (g) to determine the magnetic field for r