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The square wire frame ABCD, with 10 turns and 20 cm side length, rotates uniformly around the rotation axis perpendicular to direction B in a uniform magnetic field with 0.2T magnetic induction, and the rotation speed is 120 R / min. when the wire frame turns 90 degrees from the position parallel to the magnetic field, the change of magnetic flux in the coil is -- WB, and the average change rate of magnetic flux in the coil is -- WB / s, The average induced electromotive force is -- V
120r/min=2r/s
W=2πf=4π
￠=nBS=10*0.04*0.2=0.08W
E=（￠－￠）/t=0.08/0.125=0.64V
E=0.64V
As shown in the figure, in the trapezoidal ABCD, AD / / BC, ab = CD, e, F, G, h are the midpoint of AB, BC, CD, Da respectively
What about the picture
In the spatial quadrilateral ABCD, e, F, G and H are the midpoint of AB, BC, CD and Da respectively, then the position relationship between BC and ad is the same
When --------, efgh is rhombic
When --------, the quadrilateral efgh is a rectangle
When --------, the quadrilateral efgh is a square
When BD = AC, efgh is rhombic;
When BD ⊥ AC, efgh is a rectangle;
When BD = AC and BD ⊥ AC, the quadrilateral efgh is a square
The rectangular metal wire frame with side length L H, resistance R and mass m passes through the uniform magnetic field area with width h and magnetic induction intensity B from top to bottom at a uniform speed to calculate the heat generated in the wire frame
The rectangular metal wire frame of this problem should move in the vertical direction. Therefore, Ampere force equals gravity. According to the kinetic energy theorem, w heat = MGH
RELATED INFORMATIONS
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