In this worksheet, we will practice calculating the magnetic force between two parallel current-carrying wires.

**Q2: **

The two long parallel wires shown in the figure carry currents in the same direction. If A and A, where cm, what is the magnetic field at point ?

- A T
- B T
- C T
- D T
- E T

**Q3: **

The figure shows two long straight horizontal wires that are parallel and a distance apart, where cm. Both wires carry a current A but in opposite directions.

What is the magnitude of the magnetic field at ?

What is the magnitude of the magnetic field at

- A T
- B T
- C T
- D T
- E T

**Q4: **

Two long straight wires are parallel and 65 cm apart. If each wire carries a current of 80 A in the same direction, what is the magnetic force per unit length exerted on each wire?

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

**Q5: **

Two long parallel wires are hung by cords of length 4.00 cm, as shown in the figure. Each wire has a mass per unit length of 30.0 g/m and they carry the same current in opposite directions. What is the current if the cords are at a angle with respect to the vertical?