A current of 10.0 mA is maintained in a single circular loop with a circumference of 2.55 m. A magnetic field of 0.715 T is directed parallel to the plane of the loop. What is the magnitude of the torque exerted by the magnetic field on the loop

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?