A. Write down a typical value for the speed of sound in air in m/s
B. Write down the accepted value for the speed of light in vacuo in m/s. Convert this to miles per second.
C. How far will a radio signal travel in a time, t, of: (give answers to 4 sig. fig.)
|
1) 1 s |
2) 20 s |
3) 40 m s |
4) 27 ms |
|
5) ½ hour |
6) 2 days |
7) 1 year |
8) 19 minutes |
D. Light from the Sun takes eight minutes to arrive at Earth. How far are we from the Sun? Express your answer in kilometres.
E. The Moon is at a distance of 400 Mm from Earth. How long did radio signals sent from the Moon's surface during the Apollo landings take to arrive on Earth?
F. Express the distance 10 l.y. (light years) in metres in standard form.
G. The bright star b Orionis (Rigel) is 8.56 x 1015 km distant from the Sun. In what year did the light which we see now coming from Rigel actually leave Rigel?
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