- #1

Physicslearner500039

- 124

- 6

- Homework Statement
- A rectangular coil of wire, 22.0 cm by 35.0 cm and carrying a current of 1.40 A, is oriented with the plane of its loop perpendicular to a uniform 1.50-T magnetic field, as shown in Fig.

(a) Calculate the net force and torque that the magnetic field exerts on the coil.

(b) The coil is rotated through a 30 Deg angle about the axis shown, with the left side coming out of the plane of the figure and the right side going into the plane. Calculate the net force and torque that the magnetic field now exerts on the coil.

- Relevant Equations
- F = IlBsin(Θ); Toque = Magnetic moment * Magnetic Field

##\vec \tau = \vec \mu \times \vec B -eq1##

## F = I \vec l \times \vec B -eq2 ##

The forces i have indicated

The magnetic moment is coming out of the page.

I am only attempting only the part (a) as of now

a. The force calculations are

F1 = 1.4*0.22*1.5 = 0.462 +X direction

F2 = 1.4*0.22*1.5 = -0.462 -X direction

F3 = 1.4*.35*1.5 = 0.735 +Y direction

F4 = 1.4*.35*1.5 = -0.735 -Y direction

The net force is 0.

b. The Torque as per eq1 cross product of magnetic moment and the magnetic field. Since they are 180 Deg apart, the Torque is 0. Since they are 180 Deg apart the system is unstable and the coil starts moving. Am I correct? Please advise.

## F = I \vec l \times \vec B -eq2 ##

I am only attempting only the part (a) as of now

a. The force calculations are

F1 = 1.4*0.22*1.5 = 0.462 +X direction

F2 = 1.4*0.22*1.5 = -0.462 -X direction

F3 = 1.4*.35*1.5 = 0.735 +Y direction

F4 = 1.4*.35*1.5 = -0.735 -Y direction

The net force is 0.

b. The Torque as per eq1 cross product of magnetic moment and the magnetic field. Since they are 180 Deg apart, the Torque is 0. Since they are 180 Deg apart the system is unstable and the coil starts moving. Am I correct? Please advise.