**Q5: **

A toroid has 250 turns of wire and carries a current of 50 A. Its inner and outer radii are 11.0 cm and 14.0 cm.

What is the value of its magnetic field at ?

What is the value of its magnetic field at ?

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

**Q7: **

A 36 ampere current flows through a solenoid with turns per meter.

What is the magnetic field inside the solenoid if its core is filled with a vacuum?

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

What is the magnetic field inside the solenoid if its core is filled with liquid oxygen at 90 K having magnetic susceptibility ?

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