Question

A pentagon is a polygon with 5 sides of equal length. Imagine a pentagon in the xy-plane with its base (one of the 5 identical sides) extending from the origin along the x-axis (for which y=0) to x = 5.55 cm. The rest of the pentagon has y>0. Now imagine that a current, i = 3.33 Amps, runs along the 4 sides of the pentagon that have y>0 (ie there is no current along the x-axis side). If a uniform magnetic field of magnitude 0.222 Tesla pointing in the positive y-direction pervades the space, then what is the force on the 4-sided wire that carries the current. Answer = _______________ Newtons.

Answer 1

Step-by-step explanation:

Imagine that current runs in all the 5 sides . In that case the pentagon will have a magnetic moment directed in z- direction . So in the magnetic field it will experience a torque equal to MB where M is magnetic moment and B is magnetic field. But net force on it will be zero.

So , force on four sides due to magnetic field will be equal and opposite to force on fifth side if current runs through it.

force on fifth side if current runs through it

= BIL

= .222 x 3.33 x .0555

= 41.03 x 10⁻³ N .