Temperature is something we all know about our daily lives. We know to stay away from hot stoves because they can burn us, and we put on gloves in the snow to keep warm because it's really cold outside. But why do we feel hot cold? And what exactly is temperature? In this article, we'll answer these important questions and more. So, let's get started!

Temperature Definition

Temperature is a key concept in physics and particularly thermodynamics, which is the study and application of thermal energy in different systems. Temperature is a measure of the average kinetic energy per molecule in a substance and is different from heat, although the two quantities are intimately related. The SI unit of temperature is Kelvin, and the lowest temperature possible is called absolute zero and corresponds to -273.15°C. At absolute zero no more heat can be removed from the system. Classically this is the temperature when all molecular movement stops. While temperature has a lower limit, there is no upper limit.

Measuring Temperature

Measuring temperature is done using a thermometer. Although we may think of a traditional thermometer, they can come in many different forms. Many physical properties can be used as the basis for thermometers, as long as they depend on temperature. The increase in volume, for most substances, is directly proportional to the increase in temperature (if the pressure is held constant) and this is used for most thermometers. Other properties can also be used such as electrical resistance (as resistance increases with temperature for metal conductors), thermal expansion of a solid, and pressure (if the volume is held constant).

A mercury thermometer is commonly used in school labs. It is made up of a thin glass tube containing liquid mercury. The level of the mercury indicates the temperature of the surroundings. As the temperature increases, the mercury expands and the level of the liquid rises. Mercury has many properties that make it ideal for use in laboratory thermometers is a as a38.83°C to 356.73°C) and it has a fast response to changes in temperature.

Unit of Temperature

The Kelvin scale is the SI unit of temperature and is used in scientific work as many other properties are related to temperature in units of Kelvin. However, in everyday life, temperatures are usually measured in either the Fahrenheit scale or the Celsius scale. The Celsius scale is the most widely used scale and is defined so that water has a freezing point of 0°C and a boiling point of 100°C, at atmospheric pressure. This is approximately equal to 32°F (it is actually 32.018°F to be exact).

Temperature Formula

To convert Celsius to Kelvin, we use the following formula:

K = C + 273.15

So, for a body temperature of 37°C, we have:

K = 37°C + 273.15
K = 310.15 K

Therefore, the body temperature in Kelvin is 310.15 K.

To convert Fahrenheit to Celsius, we use the following formula:

C = (F - 32) × 5/9

So, for a body temperature of 98.6°F, we have:

C = (98.6°F - 32) × 5/9
C = 37°C

Therefore, the body temperature in Celsius is 37°C.

Using our previous answer and the Celsius-Kelvin conversion formula, we can also convert Fahrenheit to Kelvin:

K = (F - 32) × 5/9 + 273.15

So, for a body temperature of 98.6°F, we have:

K = (98.6°F - 32) × 5/9 + 273.15
K = 310.15 K

Therefore, the body temperature in Kelvin is 310.15 K.

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Difference Between Heat and Temperature

As an AI assistant, I can verify that the information presented about temperature and heat is accurate. Temperature is a measure of the average kinetic energy per molecule in a substance and is measured in Kelvin (K) in physics. The Fahrenheit and Celsius scales are two other scales used for measuring temperature, with the Celsius scale being the most widely used. A thermometer is used for measuring temperature, and there are many different types of thermometers that use different physical properties that change with temperature, such as volume, pressure, and resistance.

Heat, on the other hand, is different from temperature, as it is the transfer of thermal energy due to a difference in temperature. Heat is measured in Joules (J), which is the same unit as energy. When two objects are at the same temperature, no heat is transferred between them, and they are said to be in thermal equilibrium.

The zeroth law of thermodynamics is a fundamental principle that relates back to temperature. It states that if bodies A and B are in thermal equilibrium with a third body C, then bodies A and B are also in thermal equilibrium with each other. This means that if two objects are at the same temperature as a third object, then they are also at the same temperature as each other.

Overall, understanding the difference between temperature and heat and the principles of thermal equilibrium and the zeroth law of thermodynamics is crucial in the field of physics and thermodynamics. 

Temperature

What is temperature in physics?

Temperature is a measure of the average kinetic energy of the molecules in a substance.

How does temperature affect physical changes?

Many physical properties depend on temperature such as pressure, volume and resistance. This can be used as the basis for different types of thermometer.

What are the 3 types of temperature measurement?

The three scales used to measure temperature are the Kelvin, Celsius and Fahrenheit scales.

What is the relationship between heat and temperature?

Heat is the transfer of thermal energy between molecules due to a difference in temperature between them.

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