Author Question: What fraction of the total energy density in a cavity filled with black body radiation at 5000 K is ... (Read 77 times)

robinn137 · **on:** Jul 29, 2018

What fraction of the total energy density in a cavity filled with black body radiation at 5000 K is in the range 5.80 1014 Hz and 5.85 1014 Hz?

A)

5
B)

10
C)

1.5
D)

1
E)

25

Question 2

An object is placed 100 cm in front of a lens of focal length 20 cm. A second lens is placed 35 cm beyond the first, this second lens having a focal length of 8.0 cm. How far past the second lens is the final image formed?

A)

40 cm
B)

35 cm
C)

100 cm
D)

6.5 cm
E)

25 cm