Calculate the magnetic field strength needed on a 220-turn square loop 22 cm on a side to create a maximum torque of 254 N·m if the loop is carrying 25 A.

An eight-turn coil encloses an elliptical area having a major axis of 40.0 cm and a minor axis of 30.0 cm (see figure). The coil lies in the plane of the page and carries a clockwise current of 5.55 A. If the coil is in a uniform magnetic field of 2.09 x 10-4 T directed toward the left of the page, what is the magnitude of the torque on the coil? Hint: The area of an ellipse is A = лab, where a and b are, respectively, the semimajor and semiminor axes of the ellipse. N•m 18 I 30.0 cm T 40.0 cm

A long solenoid of 50 cm length having 100 turns carries a current of 2.5 A. The magnetic field at the centre of the solenoid is: (Ho = 47 x 10-7TmA-1)

A single-turn rectangular wire loop measures 6.00 cm wide by 10.0 cm long. The loop carries a current of 3.00 A. The loop is in a uniform magnetic field with B = 5.00 x 10-3 T. Taking torques about an axis, parallel to either side of the rectangular loop, that maximizes the torque, what is the magnitude of the torque exerted by the field on the loop if the direction of the magnetic field is described as the following? (a) parallel to the short sides of the loop N. m (b) parallel to the long sides of the loop N. m (c) perpendicular to the plane of the loop N. m