The magnetic field of the earth is approximately 3×10−5 T. At what distance from a long straight wire carrying a steady current of 10 A is the field equal to 10 percent of the earth’s field? Suggest at least two ways to help reduce the effect of electrical circuits on the navigation compass in a boat or airplane.

A simple generator can be made by attaching a square armature to the axle of your hamster’s exercise wheel, where the armature turns between the poles of a permanent magnet. You wish to use this device to operate a reading light (not shown) that requires a peak voltage of 15V and power of 25W. The magnetic field has strength B = 0.50 T, the square armature has sides of 10cm, and it contains 100 turns of wire. The bulb plus armature wire have a total resistance of 7Ω in the circuit.   a) What is the peak magnetic flux through the square armature as it turns, and at what point in the revolution does this happen?  b) ) How fast in revolutions per minute does the hamster have to run to produce the 15V peak output?(Hint: recall that ω = 2π f.)

X S xxx/qa/aubormg/answer Chegg Home Practice Q&A My solutions A conducting wire loop with 4 m² area is spinning inside a magnetic field of 0.001 T while 25 A of electric current is flowing through it. What is the torque will it feel when its area direction (normal to the surface) is at an angle of 600 with respect to the magnetic field lines? Show Transcribed Text

(2.) A battery is connected to a wire which is wrapped around a cylinder as shown in order to create a series of current loops. What direction is the magnetic field created by the current through the wire at the center of the current loops? G B + (e) (b) (d) B too B B