Superlesson
Project 2-1

Superlesson
Project 2-2

Superlesson
Project 2-3

Algebra

Chapter 2
Patterns, Change, and Expressions

Relationships in science are often expressed using the language of algebra. In the following explorations, you'll use algebra to investigate temperature, an important topic in the science of physics.

Part A, Using Variables and Expressions

1. You're probably familiar with the Fahrenheit and Celsius temperature scales. Temperatures in science are often expressed using the Kelvin scale. Read the first paragraph on the Scales of temperature Web site then answer the questions below.

a. Using the rounded figure instead of the "precise" figure, describe the relationship between the Celsius and Kelvin scales.

b. If the air temperature is C degrees Celsius, what is the Kelvin temperature?

c. If the temperature of a liquid is n degrees Kelvin, what is the Celsius temperature?

d. Complete the table.

Celsius (C)		0	10	20	30	40	50
Kelvin (K)

e. Write each pair of values as an ordered pair. Then plot the ordered pairs on a coordinate plane.

f. Are Celsius and Kelvin temperatures directly or inversely related? How do you know?

 

Part B, Evaluating Expressions

2 . One formula relating Celsius and Fahrenheit temperatures is
C = f(5(F ­ 32),9) where C is Celsius temperature and F is Fahrenheit temperature. Find the hottest temperature ever recorded on earth on the Death Valley Web site.

a. What is the hottest temperature in degrees Celsius? Round to the nearest degree.

b. Write the earth's record hot temperature in degrees Kelvin.

c. Celsius and Fahrenheit temperatures are also related by the formula F = 1.8C + 32. Find the boiling point of copper at the Web elements site. Write the temperature in degrees Celsius. Then convert it to the Fahrenheit scale.

d. Sound travels faster in hot air than it does in cool air. The velocity of sound and Kelvin temperature are related by the formula K = f(v2,404), where K is Kelvin temperature and v is the speed of sound in meters per second. Find the Kelvin temperature at the surface of the planet Mercury, where on a hot day sound may travel 560 meters per second.

e. Write Mercury's surface temperature in degrees Celsius and degrees Fahrenheit.