When the number of turns in a solenoid and its length are both ...

[lak]

When the number of turns in a solenoid and its length are both doubled, the ratio of the magnitude of the new magnetic field inside to the magnitude of the original magnetic field inside is:
 a. 0.25
  b. 0.50
  c. 1
  d. 2
  e. 4

Question 2

A long solenoid (1 000 turns/m) carries a current of 25 mA and has an inside radius of 2.0 cm. A long wire which is parallel to and 4.0 cm from the axis of the solenoid carries a current of 6.0 A. What is the magnitude of the magnetic field at a point on the axis of the solenoid?
 a. 51 mT
  b. 61 mT
  c. 43 mT
  d. 81 mT
  e. 1.4 mT

[duke02]

Answer to Question 1

C

Answer to Question 2

C

[lak]

Thank you!

[duke02]

Always glad to help...