The embroiderer should avoid using a ”knot” when starting or ending an embroidery thread. Knots can create lumps in the fabric and affect the smoothness of the design. Instead, it is recommended to use a method such as securing the thread by weaving it through the stitches or using a small hidden stitch at the start and end of the thread to avoid visible knots.
Draw the pattern of the magnetic field lines for the two parallel straight conductors carrying current of same magnitude 'I' in opposite directions as shown. Show the direction of magnetic field at a point O which is equidistant from the two conductors. (Consider that the conductors are inserted normal to the plane of a rectangular cardboard.)