Question 3: Calculate
wavelength/diameter for each, pick the smallest.
a.A 2.3 meter
telescope operating at 2 microns (like WIRO): 9x10-7
b.The Hubble Space Telescope (2.5
meter) at 150 nanometers: 6x10-8
c.The Very Large Array (36 km) at
43 GHz (0.65 cm): 1.8x10-7
d.The 10-meter Keck telescope at
500 nanometers: 5x10-8
Question 4: You
identify the Balmer series absorption lines in the spectrum of a hot type O star,
but notice that the lines are shifted from their laboratory wavelengths.
For instance, H-beta, normally seen at 486 nm appears at 488 nm. What
can you deduce about the motion of this star relative to Earth? USE
THE DOPPLER EQ:
v/c = (λobs/λrest) – 1;
v/c = (488/486) –
1 = 0.004115
V = 0.004 x 300,000
km/s = 1200 km/s away
from us (c)
Question 5: ALL
statements are true, Kirchoff’s Laws and Balmer Lines.