1. Measuring Temperature
Chapter 5
Measuring Temperature

2. LecturePLUS Timberlake
Temperature
Particles are always moving.
When you heat water, the water molecules move faster.
When molecules move faster, the substance gets hotter.
When a substance gets hotter, its temperature goes up.
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3. LecturePLUS Timberlake
Learning Check
Suppose you place water in a freezer.
A. The water particles move
1) faster 2) slower ) the same
B. The water will get
1) hotter 2) colder ) stay the same
C. The temperature of the water will be
1) higher 2) lower ) the same
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4. LecturePLUS Timberlake
Solution
Suppose you place water in a freezer.
A. The water particles move
2) slower
B. The water will get
2) colder
C. The temperature of the water will be
2) lower
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5. LecturePLUS Timberlake
Temperature
Measures the hotness or coldness of an object
Determined by using a thermometer that contains a liquid that expands with heat and contracts with cooling.
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6. LecturePLUS Timberlake
Temperature Scales
Fahrenheit Celsius Kelvin
Water boils _____°F _____°C ______K
Water freezes _____°F _____°C ______K
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7. LecturePLUS Timberlake
Temperature Scales
Fahrenheit Celsius Kelvin
Water boils °F °C K
Water freezes 32°F °C K
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8. Units of Temperature between Boiling and Freezing
Fahrenheit Celsius Kelvin
Water boils °F °C K
180° °C K
Water freezes 32°F °C K
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9. LecturePLUS Timberlake
Learning Check
A. Temperature of freezing water
1) 0°F ) 0°C ) 0 K
B. Temperature of boiling water
1) 100°F ) 32°F ) 373K
C. Number of Celsius units between the
boiling and freezing points of water
1) ) ) 273
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10. LecturePLUS Timberlake
Solution
A. Temperature of freezing water
2) 0°C
B. Temperature of boiling water
3) 373K
C. Number of Celsius units between the
boiling and freezing points of water
1) 100
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11. LecturePLUS Timberlake
Fahrenheit Formula
180°F = °F = 1.8°F °C °C 1°C
Zero point: °C = 32°F
°F = 9/5 T°C or
°F = 1.8 T°C
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12. LecturePLUS Timberlake
Celsius Formula
Rearrange to find T°C
°F = 1.8 T°C
°F = 1.8T°C ( )
°F = 1.8 T°C
°F = T°C
1.8
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13. Temperature Conversions
A person with hypothermia has a body temperature of 29.1°C. What is the body temperature in °F?
°F = (29.1°C)
exact tenth's exact =
= 84.4°F
tenth’s
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14. LecturePLUS Timberlake
Learning Check
The normal temperature of a chickadee is 105.8°F. What is that temperature in °C?
1) °C
2) °C
3) °C
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15. LecturePLUS Timberlake
Solution
3) 41.0 °C
Solution:
°C = (°F - 32)
1.8
= ( )
= 73.8°F
1.8° = °C
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16. LecturePLUS Timberlake
Learning Check
Pizza is baked at 455°F. What is that in °C?
1) 437 °C
2) 235°C
3) 221°C
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17. LecturePLUS Timberlake
Solution
Pizza is baked at 455°F. What is that in °C?
2) 235°C
( ) = 235°C
1.8
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18. LecturePLUS Timberlake
Learning Check
On a cold winter day, the temperature falls to -15°C. What is that temperature in °F?
1) 19 °F
2) 59°F
3) 5°F
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19. LecturePLUS Timberlake
Solution
3) 5°F
Solution:
°F = 1.8(-15°C) + 32 =
= 5°F
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20. LecturePLUS Timberlake
Kelvin Scale
On the Kelvin Scale
1K = 1°C
0 K is the lowest temperature
0 K = °C
K °C
K = °C
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21. LecturePLUS Timberlake
Learning Check
What is normal body temperature of 37°C in kelvins?
1) 236 K
2) K
3) 342 K
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22. LecturePLUS Timberlake
Solution
What is normal body temperature of 37°C in kelvins?
2) 310 K
K = °C + 273
= 37 °C
= 310. K
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