Two thin slits are 6.00 m apart. Monochromatic coherent light ...

[tiara099]

Two thin slits are 6.00 m apart. Monochromatic coherent light falls on these slits, and produces a fifth-order bright interference fringe at an angle of 32.3 away from the centerline. What is the wavelength of the light?
 
  A) 164 nm
  B) 416 nm
  C) 614 nm
  D) 641 nm

Question 2

A concrete wall of a cold storage room measures 3.0 m high, 5.0 m wide, and 20 cm thick. The inside wall is to be covered by a layer of wood in order to reduce the rate of thermal energy flow through the wall by 90 percent.
 
  The inner surface of the wooden wall is maintained at -10C and the outer surface of the concrete wall is at 20C. The thermal conductivities of concrete and wood are 0.80 W/m  K (concrete) and 0.040 W/m  K (wood). What is the temperature difference across the layer of wood?
  A) 24 C
  B) 25 C
  C) 26 C
  D) 27 C
  E) 28 C

[Dnite]

Answer to Question 1

D

Answer to Question 2

D