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
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??? m |
= |
975 mi |
X |
1.621 km |
X |
1000 m |
X |
1 hr |
= |
439 m |
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1 sec |
1 hr |
1 mi |
1 km |
3600 sec |
1 sec |
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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!
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??? tab |
= |
1 kg |
X |
1000 g |
X |
15.4 grain |
X |
1 tab |
= |
3080 tab |
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1 |
1 |
1 kg |
1 g |
5 grain |
1 |
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3. A parsec is the distance light travels in 3.26 years. Given the velocity of light, 3.00 x 108 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
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??? km |
= |
1 parsec |
X |
3.26 yr |
X |
365 day |
X |
24 hr |
X |
3600 sec |
X |
3.00 X 108
m |
= |
3.08 X 1013 km |
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1 |
1 |
1 parsec |
1 yr |
1 day |
1 hr |
1 sec |
1 |
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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 Mini-Ipod holds only 4 gigabytes of recordings, could I use a mini for my project?
____???_____ Gb = 1400 programs
Change programs to megabytes to gigabytes
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??? Gb |
= |
1400 Program |
X |
5 Mb |
X |
1 Gb |
= |
6.84 Gb |
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1 |
1 |
1 Program |
1024 Mb |
1 |
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