Wednesday, November 10, 2010

Review #30

Just making sure we covered everything, I chose Dimensional Analysis because we covered it so early some of us may have forgotten it by now. Here are some questions you can try out and the answers are listed at the bottom.

Here are the conversions you will need:
1 miles= 5280 ft.

1 inch= 2.54 cm.
1 lightyear= 9.467x10^15m
1 parsec= 1.91738x10^13 mi.


1) 5.0 in = __ mm
2) 123.0 ng= __ Mg
3) How many parsecs make up a lightyear?

Key:
1) 127
5in. x 2.54cm/1 in. x 1m/100cm x 1000mm/1m

2)1.230x10^-13
123.0ng x 1g/10^9ng x 10^-6Mg/1g

3) 0.3068
9.467x10^15m x 100cm/1m x 1in./2.54cm. x 1ft./12in. x 1mi./5280ft. x 1 parsec/1.91738x10^13