UNIT CONVERSION WITH EQUATION
A 55.9-kg person displaces 57.2 L of water when submerged in a water tank. What is the density of the person in grams per cubic centimeter?
Solving Numerical Problems | |
1. SORT
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GIVEN: m = 55.9 kg
V = 57.2 L FIND: density in g/cm^3 |
2. STRATEGIZE
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SOLUTION MAP
m, V\underset{ d= \frac{m}{V}}{\longrightarrow } d
RELATIONSHIPS USED d= \frac{m}{V} (definition of density) |
3. SOLVE
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The equation is already solved for the find quantity. Convert mass from kilograms to grams.
m=55.9 \cancel{ kg} \times \frac{1000 g}{1 \cancel{ kg}}
= 5.59 \times 10^4 g Convert volume from liters to cubic centimeters. V = 57.2 \cancel{L}\times \frac{1000 \cancel{mL}}{1 \cancel{L}} \times \frac{1 cm^3}{1 \cancel{mL}}= 57.2 \times 10^3 cm^3 Calculate density. d= \frac{m}{V}=\frac{55.9 \times 10^3 g}{57.2 \times 10^3 cm^3}= 0.9772727 \frac{g}{cm^3}
= 0.977 \frac{g}{cm^3} |
4. CHECK
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The units are correct. Because the mass in kilograms and the volume in liters are very close to each other in magnitude, it makes sense that the density is close to 1 g/cm^3. |