A CD player uses a laser whose light frequency is 3.85 1014 Hz. ...

[cdr_15]

A CD player uses a laser whose light frequency is 3.85  1014 Hz. Calculate the energy, in joules, of the photons.

Question 2

Two solenoids are each made of 2 000 turns of copper wire per meter. Solenoid I is 2 m long, while solenoid II is 1 m long. When equal currents are present in the two solenoids, the ratio of the magnetic field BI along the axis of solenoid I to the magnetic field BII along the axis of solenoid II, BI/BII, is
 a. 1/4.
  b. 1/2.
  c. 1.
  d. 2
  e. 4.

[dudman123]

Answer to Question 1

2.55  1019 J

Answer to Question 2

c

[cdr_15]

Thank you!

[dudman123]

Always glad to help...