Module 7: Heat and Temperature
In this lesson, you will learn about the transfer of thermal energy, how it is different from work, the 1st Law of Thermodynamics, heat transfer to change temperature and specific heat, and heat to change phase (latent heat).
CC7.1 Solve problems involving heat and temperature
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LO7.1.1: Perform unit conversions between kelvin, degrees Celsius, and degrees Fahrenheit
LO7.1.2 Investigate the meaning of thermal equilibrium
LO7.1.3 Compute the expansion of heated or cooled objects
LO7.1.4 Compare and contrast the different states of matter
LO7.1.5 Practice using the ideal gas law to find the state of an ideal gas
★ LO7.1.6 Differentiate between thermal energy, temperature, and heat
★ LO7.1.7 Solve problems involving heat transfer, specific heat, and latent heat
LO7.1.8 Create machine diagrams and perform calculations from them
Read Chapter 4 of Physical Science, 13th edition by Bill Tillery McGraw Hill Education
Time: 10:51
Topics: In this lecture, we will cover heat, heat capacity and latent heat, and the First Law of Thermodynamics.
The easiest way to understand the difference between heat and temperature is to imagine a large swimming pool. Beside the pool is a table with a glass of water. When you take a thermometer and test the water temperature, but are the same temperature. Now imagine that you are required to raise the temperature 1 degree. It would not be too hard to do that with the glass of water. However, raising the temperature for water in the pool would be quite a challenge. Heat involves the consideration of the mass involved.
Time
Topic: Q = mc∆T
Some substances experience heat transfer to it very rapidly while other substances do not take on the heat from its surroundings very fast. Think of a styrofoam cooler on a hot summer day. It can keep food cold for a long time compared to if you put something into a metal pot in the same environment. The styrofoam is a poor conductor of heat. The metal is a good conductor of heat.
The Nobel Prize in Physics 2021 will be awarded to three scientists: Syukuro Manabe and Klaus Hasselmann “for the physical modelling of Earth’s climate, quantifying variability and reliably predicting global warming”, and Giorgio Parisi “for the discovery of the interplay of disorder and fluctuations in physical systems from atomic to planetary scales” Their work is very interesting, and I encourage you to read more about it.
Print off these equation sheets to help you complete the mastery assessments.
PROMT A 1000 kg car is moving at 90.0 km/h. How many kilocalories are generated when the car brakes to stop?
LO7.1.7 Solve problems involving heat transfer, specific heat, and latent heat
Answer
Answer: 74.7 kilocalories
Not what you got? Watch the video to see where you went wrong.
Time: 8:00
PROMT How much heat will be supplied to a 500 g pan to raise temperature from 20.0℃ to 100.0℃ if the pan is made of iron and aluminum?
LO7.1.7 Solve problems involving heat transfer, specific heat, and latent heat
Answer
Answer:
Not what you got? Watch the video to see where you went wrong.
Time: 12:53
PROMT What is the specific heat of a 2 kg metal sample if 1.2 kcal is needed to increase the temperature from 20.0℃ to 40.0℃?
LO7.1.7 Solve problems involving heat transfer, specific heat, and latent heat
Answer
Answer: 0.03
Not what you got? Watch the video to see where you went wrong.
Time: 5:34