Current Loops

What is the net force on a square loop of current when it is placed in a uniform magnetic field pointing out of the screen?

• The net force is not zero.

• The net force depends on the current in the loop.

• The net force is zero.

• The net force depends on the side length of the square loop.

In the context of a square loop of current in a magnetic field, what does the expression F = ILB represent?

• The net force on the loop

• The force on each side of the loop

• The magnetic field strength

• The current in the loop

What will happen to the square loop of current in the magnetic field over time?

• It will remain stationary.

• It will rotate.

• It will be pulled out of the magnetic field.

• It will expand in size.

What is the net torque about the center of a square loop of current when the loop is in the xy plane and the magnetic field B is parallel to the xz plane?

• τ = IL^2Bsinθ

• τ = ILBsinθ

• τ = 2ILBsinθ

• τ = ILBcosθ

Which of the following best describes the magnetic dipole moment (μ) for a current loop of area A and current I?

• μ = I/A

• μ = IA

• μ = A/I

• μ = I + A

According to the right-hand rule, the direction of the area vector (A) for a current loop is given by:

• The direction of the magnetic field

• The direction of the current

• The direction opposite to the current

• The direction determined by the curl of the fingers when the thumb points in the direction of the current

What does the magnetic dipole moment (μ) tend to do in a uniform magnetic field (B)?

• It tends to align itself with B

• It tends to align itself opposite to B

• It remains perpendicular to B

• It rotates randomly

What is the potential energy (U) of a magnetic dipole in a uniform magnetic field?

• U = μBcosθ

• U = -μBcosθ

• U = μBsinθ

• U = -μBsinθ

At what angle θ is the potential energy (U) of a magnetic dipole minimum and indicates a stable equilibrium in a uniform magnetic field?

• θ = 90°

• θ = 180°

• θ = 0°

• θ = 45°

What do bar magnets and current loops have in common according to the image?

• They both generate electric fields.

• They both have the same shape.

• They are both magnetic dipoles.

• They both repel magnetic fields.