电流由长直导线流入一电阻均匀分布的金属矩形框架,再从长直导线流出,设图中https://bgk-photo.cdn.bcebos.com/d4628535e5dde71144d4d396b7efce1b9d166148.jpg处的磁感应强度为https://bgk-photo.cdn.bcebos.com/8d5494eef01f3a29ccce45ae8925bc315c607c48.jpg则A、spanB、https://bgk-photo.cdn.bcebos.com/622762d0f703918f56ca20ab413d269759eec4bc.jpgC、;D、spanE、https://bgk-photo.cdn.bcebos.com/908fa0ec08fa513ddf8f71bf2d6d55fbb2fbd9ae.jpgF、;G、spanH、https://bgk-photo.cdn.bcebos.com/58ee3d6d55fbb2fbbd0e45735f4a20a44623dcae.jpgI、;J、spanK、https://bgk-photo.cdn.bcebos.com/42166d224f4a20a4440421a680529822720ed0bc.jpgL、I分开,算出每个支路上的电流大小,然后按照M、https://bgk-photo.cdn.bcebos.com/6c224f4a20a446230aeeb8038822720e0cf3d7ae.jpgN、计算。O、注意要会算具体的值。