You may use a calculator.
Please use the Unit Analysis or Dimensional Analysis method to solve ONLY TWO
of the following word problems:
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1. An oxygen molecule travels 975 mi/hr at room temperature. There are 5280 ft = 1 mi; 12 in = 1 ft, 2.54 cm = 1 in, 1.621 km = 1 mi, and 3600 sec = 1 hr. What is the velocity in meters per second?
____???____ m/sec = 975 mi/hr
1.
On the Numerator:
Change m to km to miles
or change m to cm to inches to feet to miles
2. then on the denominator:
change hours to seconds or change
hours to minutes to seconds



??? m 
= 
975 mi 
X 
1.621 km 
X 
1000 m 
X 
1 hr 
= 
439 m 








1 sec 
1 hr 
1 mi 
1 km 
3600 sec 
1 sec 


2. If one gram is equal to 15.4 grains. How many 5.00 grain aspirin tablets may be made from 1.00 kilogram of aspirin?
____???_____ tab = 1.00 kg
Change kg to g to grains to tablets!



??? tab 
= 
1 kg 
X 
1000 g 
X 
15.4 grain 
X 
1 tab 
= 
3080 tab 








1 
1 
1 kg 
1 g 
5 grain 
1 


3. A parsec is the distance light travels in 3.26 years. Given the velocity of light, 3.00 x 10^{8} m/sec, how many kilometers does light travel in one parsec?
____???_____ km = 1 parsec
change parsec to years to days to hours to minutes to seconds to meters then to
kilometers



??? km 
= 
1 parsec 
X 
3.26 yr 
X 
365 day 
X 
24 hr 
X 
3600 sec 
X 
3.00 X 10^{8}
m 
= 
3.08 X 10^{13} km 










1 
1 
1 parsec 
1 yr 
1 day 
1 hr 
1 sec 
1 


4. I have 1400 radio programs I want to put on an Apple Ipod. Each program requires 5 megabytes of disk space. If there are 1024 megabytes in a gigabyte. How many gigabytes of disk space do I need minimum to store all my programs on the IPod. The MiniIpod holds only 4 gigabytes of recordings, could I use a mini for my project?
____???_____ Gb = 1400 programs
Change programs to megabytes to gigabytes



??? Gb 
= 
1400 Program 
X 
5 Mb 
X 
1 Gb 
= 
6.84 Gb 







1 
1 
1 Program 
1024 Mb 
1 

