The sun has apparent brightness B at the earth, which is 1.5 108 km away.
What would be the apparent brightness of the sun at Pluto, which is 6.0 109 km from the sun?
A) 0.063 B B) 0.00063 B C) 0.025 B D) 0.25 B
Question 2
The rate of energy flow per unit area of a sinusoidal electromagnetic wave has an average value of 0.601 W/m2.
What is the maximum value of the magnetic field in the wave? (c = 3.00 108 m/s, 0 = 4 10-7 T m/A, 0 = 8.85 10-12 C2/N m2 )
A) 3.55 10-8 T B) 7.09 10-8 T C) 9.81 10-8 T D) 1.42 10-7 T E) 5.02 10-8 T