**Q1: **

A 4.0-cm by 6.0-cm rectangular current loop carries a current of 10 A. What is the magnetic dipole moment of the loop?

**Q2: **

A conducting loop has 50 square turns with sides 15 cm long. The loop is placed in a uniform 0.80-T magnetic field. Find the current through the loop needed to create a maximum torque of 9.0 N.m.

**Q3: **

A 5.0-m section of a long, straight wire carries a current of 10 A while in a uniform magnetic field of magnitude T.

Calculate the magnitude of the force on the section if the angle between the field and the direction of the current is .

**Q4: **

A circular coil of wire of radius 5.0 cm has 20 turns and carries a current of 2.0 A. The coil lies in a magnetic field of magnitude 0.50 T that is directed parallel to the plane of the coil.

What is the magnetic dipole moment of the coil?

What is the torque on the coil?

**Q5: **

The current through a circular wire loop of radius 10.0 cm is 5.0 A. The wire loop is in a 0.20-T magnetic field that is directed at a angle to the loop’s magnetic dipole moment.

Calculate the magnetic dipole moment of the loop.

What is the torque on the loop?

What is the potential energy of the dipole?

**Q6: **

The magnetic dipole moment of the iron atom is about
A⋅m^{2}.

Calculate the maximum magnetic dipole moment of a domain consisting of iron atoms.

- A A⋅m
^{2} - B A⋅m
^{2} - C A⋅m
^{2} - D A⋅m
^{2} - E A⋅m
^{2}

What would be the current in a single circular loop of wire with diameter 1.0 cm that produced the same dipole moment as that produced by iron atoms?

**Q7: **

A proton has a magnetic field due to its spin. The field is equivalent to that created by a circular current loop m in radius that carries a current of A. Find the magnitude of the maximum torque on a proton that can be produced by a 2.50-T magnetic field.

- A N.m
- B N.m
- C N.m
- D N.m
- E N.m