Temperature and Heat

Purpose:

• Examine the relationship between Fahrenheit, Celsius, and Kelvin
• Learn how to report an answer in physics class with uncertainty and standard deviation
• Observe the behavior of heat transfer 
• Understand factors that affect heat transfer processing

Examine the relationship between Fahrenheit, Celsius, and Kelvin

We use data given and graph to figure out the relationship between Fahrenheit and Celsius. Moreover, we also investigate the relationship between kelvin and celsius by converting the room temperature from celsius to kelvin

How to report an answer in physics class

We collect the results of room temperature in kelvin scale from all groups in class, then calculate the average and standard deviation. We learn that it is good for physics students to include uncertainty in our answers.

Heat Transfer and Thermal Equilbrium

Professor prepare a cup of hot and cold water, mix them together, and connect it to Logger Pro to observe the change in temperature.

Determine final temperature

Given the same substance (water), we were asked to calculate the final temperature. We applied the concept that the amount of heat released from hot object equal the amount of heat absorbed from cold object. We manage to calculate the final temperature and predict our uncertainty (the answer on the left). On the right side of the board, the question gives the different mass and ask for the final temperature. We apply the same concept to calculate final temperature.

Factors affect heat transfer.

Professor asks to come up with at least four or five factors affect heat transfer, and our group got six ideas. Compared to other groups, the main four factors are surface area, the difference in temperature,  the thickness of the object, and mass of the object.

 Calculate heat transfer

We were asked to calculate the heat flow through the system of a copper and aluminum bar. Given the length, heat conductivity, and the change in temperature, we manage to calculate the heat flow through the shoe system. 

Part 2 and 3 of the question asks to find the heat flow for each bar. Since the heat flow of each bar is equal the heat flow of the whole system, we get the same answer like part 1. Then we calculate the temperature at the interface. With the heat flow just found for aluminum bar, we find the temperature at the interface around 67 celsius degree

Examine the change in temperature as a function of time

The apparatus includes an immersion heater, a power watch, a beaker, water, and Logger Pro. We connect the immersion heater to the power watch, then turn it on. The other side of immersion heater is put into a beaker which contains 200mL water initial. We stir the water harmoniously and observe the change in temperature in Logger Pro.

Record the power on the power watch in 20 seconds, then makes another column in Logger Pro to calculate heat in order to make a graph of temperature vs. heat. 

This is the graph of temperature vs. heat. As you can see, there is almost a linear relationship between heat and temperature. In other words, the change in heat is proportional to the change in temperature.

The heat conductivity of rubber

In this experiment, we have a ballon held stable by a clamp. We use a gun heater to fire up water inside the ballon, and see how long it takes for the ballon to blow up. Since the ballon is made out of rubber which is a poor heat conductivity, it takes around 15 seconds for the ballon to blow up regardless of the strong heat from the gun. 

Conclusion:

In the first lab, we basically examine the relationship between Fahrenheit, Celsius, and Kelvin. Moreover, we also test factors that affect heat transfer process. Thermal equilibrium is also an important topic in this lab. It relates to the calculation of final temperature and heat flow. We also perform an experiment to check the heat conductivity of rubber. Finally, we make another experiment to observe the change in temperature as a function of time as well as heat. From that, we come up with the linear relationship between temperature and heat thanks to Logger Pro.