Grade 10
  1. Mechanics  1.1. Dynamics  1.1.1. Motion in one dimension  1.1.2. Motion in two dimensions  1.1.3. Displacement and Distance  1.1.4. Speed and Velocity  1.1.5. Acceleration  1.1.6. Graphical representation of motion  1.1.7. Equations of motion  1.1.8. Free fall and acceleration due to gravity  1.1.9. Projectile motion  1.1.10. Relative speed  1.2. Dynamics  1.2.1. Newton's Laws of Motion  1.2.2. Inertia and mass  1.2.3. Force and its types  1.2.4. action and reaction force  1.2.5. Friction and its effects  1.2.6. Coefficient of friction  1.2.7. Circular motion  1.2.8. Centripetal force and centripetal acceleration  1.2.9. Momentum and Impulse  1.2.10. Conservation of momentum  1.2.11. Newton's third law and applications  1.3. Work, Energy and Power  1.3.1. Work done by the force  1.3.2. Work–energy theorem  1.3.3. Kinetic energy  1.3.4. Potential energy  1.3.5. Mechanical energy  1.3.6. Energy Conservation  1.3.7. Power and efficiency  1.3.8. Renewable and non-renewable energy sources  1.4. Gravitational force  1.4.1. Newton's law of universal gravitation  1.4.2. Gravitational field and field strength  1.4.3. Acceleration due to gravity on different planets  1.4.4. Kepler's laws of planetary motion  1.4.5. Orbits and satellites  1.4.6. Weight and apparent weight  1.4.7. Gravitational potential energy
  2. Properties of matter  2.1. States of matter  2.1.1. Solid, liquid and gas  2.1.2. Molecular structure of matter  2.1.3. Intermolecular forces  2.1.4. Plasma and Bose–Einstein condensate  2.2. Pressure  2.2.1. Definition of Pressure  2.2.2. Pressure in liquids  2.2.3. Atmospheric pressure  2.2.4. Pascal's principle  2.2.5. Archimedes' Principle and Buoyancy  2.2.6. Surface tension and capillarity  2.3. Elasticity  2.3.1. Hooke's law  2.3.2. Stress and strain  2.3.3. Elastic Limit and Modulus of Elasticity  2.3.4. Applications of Elasticity
  3. Thermal physics  3.1. heat and temperature  3.1.1. Difference Between Heat and Temperature  3.1.2. Temperature scale  3.1.3. Thermal expansion  3.1.4. Thermal equilibrium  3.2. Heat transfer  3.2.1. Conductivity  3.2.2. Convection  3.2.3. Radiation  3.2.4. Insulation and its applications  3.3. Thermal properties of matter  3.3.1. Specific heat capacity  3.3.2. Latent heat and phase change  3.3.3. Boiling and Melting Point  3.3.4. Heat engines and refrigeration  3.4. Laws of Thermodynamics  3.4.1. Zeroth law of thermodynamics  3.4.2. First law of thermodynamics  3.4.3. Second law of thermodynamics  3.4.4. Carnot cycle
  4. Waves and optics  4.1. Nature and properties of waves  4.1.1. Types of waves in nature and properties of waves  4.1.2. Transverse and longitudinal waves  4.1.3. Wave parameters  4.1.4. Reflection and refraction of waves  4.1.5. Superposition and Interference  4.1.6. Standing Waves and Resonance  4.1.7. Doppler effect  4.2. Sound waves  4.2.1. Characteristics of sound waves  4.2.2. Speed of sound in different mediums  4.2.3. Applications of sound waves  4.2.4. Ultrasound and its uses  4.3. Light Waves and Optics  4.3.1. Nature of light  4.3.2. Reflection of light  4.3.3. Laws of reflection  4.3.4. Mirrors and Image Formation  4.3.5. Refraction of light  4.3.6. Snell's Law  4.3.7. Lenses and Image Formation  4.3.8. Total internal reflection and critical angle  4.3.9. Optical fibre  4.4. Optical Instruments  4.4.1. Microscope  4.4.2. Telescope  4.4.3. Human eye and vision defects  4.4.4. Camera and its working principle
  5. Electricity and Magnetism  5.1. Electrostatics  5.1.1. Electric charge and its properties  5.1.2. Conductors and Insulators  5.1.3. Coulomb's law  5.1.4. Electric field and field lines  5.1.5. Electric potential and potential difference  5.1.6. Capacitors and Capacitance  5.2. Current Electricity  5.2.1. Electric current and its measurement  5.2.2. Ohm's law  5.2.3. Resistance and resistivity  5.2.4. Series and Parallel Circuits  5.2.5. Electric power and energy  5.2.6. Kirchhoff's Laws  5.3. Magnetism and Electromagnetism  5.3.1. Magnetic field and field lines  5.3.2. Magnetic effects of electric current  5.3.3. Electromagnetic induction  5.3.4. Faraday's laws of electromagnetic induction  5.3.5. Transformers and Applications  5.3.6. AC and DC current
  6. Modern Physics  6.1. Nuclear physics  6.1.1. Structure of the atom  6.1.2. Bohr's atomic model  6.1.3. Electron Energy Levels  6.1.4. X-rays and applications  6.2. Radioactivity  6.2.1. Types of radiation  6.2.2. Half-life and radioactive decay  6.2.3. Nuclear reactions and applications  6.2.4. Fission and Fusion  6.3. Quantum physics  6.3.1. Wave–particle duality  6.3.2. Photoelectric effect  6.3.3. Energy quantization  6.3.4. Heisenberg's uncertainty principle
  7. Electronics and Communication  7.1. Semiconductors  7.1.1. Conductors, Insulators and Semiconductors  7.1.2. Diodes and their applications  7.1.3. Transistors and Logic Gates  7.1.4. LEDs and photodiodes  7.2. Communication Systems  7.2.1. Basics of communication  7.2.2. Analog and digital signals  7.2.3. Wireless and optical fibre communication  7.2.4. Radio Waves and Modulation

Grade 10 → Thermal physics → heat and temperature ↓


Temperature scale


In the world of thermal physics, it is very important to understand temperature and the scales used to measure it. Temperature is a measure of the average kinetic energy of the particles in a substance. It tells us how hot or cold something is. Different scales are used to measure temperature around the world, each with significance depending on the context in which they are used.

What is the temperature?

Before discussing the temperature scale, let us first understand what temperature is. Temperature is one of the key physical properties in physics, which reflects the thermal state of matter. Basically, it is an indirect measure of how energetic particles are in a substance. The more kinetic energy the particles have, the higher the temperature of the substance.

Main temperature scale

There are several temperature scales used around the world, but the three most common are Celsius, Fahrenheit, and Kelvin. Let's take a closer look at each:

Celsius scale

The Celsius scale, also known as the centigrade scale, is the most widely used temperature scale worldwide. This scale sets the freezing point of water at 0 degrees Celsius (°C) and the boiling point at 100 °C under standard atmospheric conditions.
The Celsius scale is based on the metric system, which is simple and intuitive, especially for scientific work.

0°C - Freezing point of water 100°C - Boiling point of water
0 °C 100 degrees Celsius

In daily life, temperature is often expressed in Celsius. For example, a hot summer day may be about 30 °C, while a cold winter day may be about -5 °C. The Celsius scale is user-friendly because each degree change on this scale is equivalent to a specific, equivalent energy change.

Fahrenheit scale

The Fahrenheit scale is used primarily in the United States. It sets the freezing point of water at 32 degrees Fahrenheit (°F) and the boiling point at 212 °F. Between these two points the scale is divided into 180 divisions.

32°F - Freezing point of water 212°F - Boiling point of water
32°F 212°F

The conversion between Fahrenheit and Celsius can be calculated using this formula:

T(°F) = T(°C) × 9/5 + 32

where T(°F) is the temperature in Fahrenheit and T(°C) is the temperature in Celsius.

For example, to convert 30°C to Fahrenheit:

T(°F) = 30 × 9/5 + 32 = 86°F

Kelvin scale

The Kelvin scale is the standard unit of temperature used in scientific contexts. It is an absolute temperature scale that begins at absolute zero, the theoretical point where all particle motion ceases. The Kelvin scale does not use degrees; it is simply "kelvin" (K).

0 K - Absolute zero

The Kelvin and Celsius scales are directly related. You can convert Celsius to Kelvin using the formula:

T(K) = T(°C) + 273.15

For example, to convert 25°C to Kelvin:

T(K) = 25 + 273.15 = 298.15 K
0's 373.15 K

Units and measurements

All the scales mentioned have specific units and are used in different scenarios:

  • Celsius: Used primarily for most temperature measuring tasks outside of the United States.
  • Fahrenheit: Used primarily in the United States and some Caribbean countries.
  • Kelvin: It is used in scientific communities around the world due to its absolute nature.

Why different scales?

Different scales exist due to historical and regional preferences. For example, the Fahrenheit scale was developed by Daniel Gabriel Fahrenheit in 1724, before the Celsius scale was introduced by Anders Celsius in 1742. The Kelvin scale was developed later in the 19th century by Lord Kelvin to provide a temperature scale that better suited the needs of science.

Interactive example

Let us consider some scenarios to understand the relationship between these scales:

  • Example 1: Freezing and boiling point
    Water freezes:
    • 0 °C
    • 32°F
    • 273.15 K
    Water boils:
    • 100 degrees Celsius
    • 212°F
    • 373.15 K
  • Example 2: Human body temperature
    The normal human body temperature is approximately:
    • 37°C
    • 98.6°F
    • 310.15 K
  • Example 3: Absolute zero
    Absolute zero, the theoretical point of complete particle stability, occurs at:
    • -273.15° Celsius
    • -459.67°F
    • 0's

Summary

Temperature scales are an important part of understanding and communicating thermal information in a variety of contexts and fields. Whether Celsius is used for everyday European weather reports, Fahrenheit in American forecasts, or Kelvin in scientific research, the end goal remains the same: to describe how hot or cold something is.


Grade 10 → 3.1.2


U
username
0%
completed in Grade 10

← Prev (3.1.1)
Difference Between Heat and Temperature
Next (3.1.3) →
Thermal expansion

Comments 



Temperature scale

https://www.physicsflow.com/g10/3.1.2?pfal=en