An ideal solenoid of radius a has n turns per unit length and ...

[ssal]

An ideal solenoid of radius a has n turns per unit length and current I. The magnetic flux _B through any area completely inside the solenoid, centered on the solenoid axis but at a 45 angle to the axis so that it touches the inside of the solenoid as shown below, is
 
 
 
   
  a.
  .
   
  b.
  .
   
  c.
  ₀a²nI.
   
  d.
  2₀a²nI.
   
  e.
  0.

Question 2

An ideal solenoid of radius a has n turns per unit length and current I. The magnetic flux _B through any circular area of radius a inside the solenoid, centered on and perpendicular to the solenoid axis, is
   
  a.
  .
   
  b.
  .
   
  c.
  ₀a²nI.
   
  d.
  2₀a²nI.
   
  e.
  0.

[Athena23]

Answer to Question 1

c

Answer to Question 2

c