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 ↓


Difference Between Heat and Temperature


It is very important to understand the concepts of heat and temperature in thermal physics. Although people often use these terms interchangeably in informal conversations, they have different meanings in physics. This explanation will guide you in understanding these differences using simple language and illustrative examples.

Defining heat

Heat is a form of energy. It is something that can move from one object to another because of a difference in temperature. When we say that something is "hot," we mean that the object is carrying a lot of heat energy. Heat flows from areas of higher temperature to areas of lower temperature.

Imagine you have a cup of hot coffee. If you touch the cup, your hand will feel warm. This warmth is because heat is being transferred from the coffee to your hand. This transfer of energy is what we call heat.

Heat transfer

Heat transfer can occur in three ways: conduction, convection, and radiation.

  • Conduction: This is when heat is transferred through direct contact. For example, if you hold a metal rod and heat one end, the other end will eventually heat up too — even if it's far from the heat source.
  • Convection: This occurs in fluids (liquids and gases) where the hotter part of the fluid rises and the cooler part sinks, creating a cycle. Imagine boiling water: the hotter water from the bottom moves up.
  • Radiation: Heat can transfer without a medium via electromagnetic waves, like when the sun warms your face.

Defining temperature

Temperature is a measure of how hot or cold something is. More scientifically, it's the average kinetic energy of the particles in a substance. When you measure temperature, you're measuring the energy per particle in the system.

If we imagine particles in a hot substance, they move quickly. In cold substances, these particles move more slowly. This motion is what creates thermal energy, and we use temperature to estimate this energy per particle.

Temperature scale

The most common scales for measuring temperature are Celsius (°C), Fahrenheit (°F), and Kelvin (K). Here's how they are used:

  • Celsius: Widely used around the world; 0°C is the temperature where water freezes, and 100°C is the temperature where water boils.
  • Fahrenheit: Used primarily in the United States; water freezes at 32°F, and boils at 212°F.
  • Kelvin: Used primarily in scientific contexts; this is an absolute scale that starts at absolute zero, which is theoretically the coldest temperature, where particles stop moving.

Heat vs Temperature

Now that we understand what heat and temperature mean separately, let's highlight their differences:

heat ≠ temperature

Although heat and temperature are related to each other, they are not the same thing. Let's see what is the difference between them:

1. Nature:

Heat is a type of energy. When energy flows due to a temperature difference, we call it heat. Temperature, on the other hand, is a measurement. It tells us the hotness or coldness of a substance.

2. Unit of measurement:

We measure heat in joules (J), which is the SI unit of energy. Temperature is measured in Celsius (°C), Fahrenheit (°F), or Kelvin (K).

3. Dependency:

Heat depends on the mass of the substance, the temperature change, and the specific heat capacity. Temperature does not depend on the mass or type of the object; it depends only on how the kinetic energy is distributed among its particles.

4. Transfer:

Heat can transfer from one object to another, but the temperature itself is not transferred. Rather, heat transfer causes a temperature change.

Visual example

To help understand, let's look at how heat and temperature work by considering water boiling.

Water at 100°C boiling point of water

In this diagram, boiling water represents a high energy state due to the high temperature. The particles are moving fast (reflected by the position of the red circles) and collide with each other. However, as long as it is boiling, the temperature remains constant at 100°C because all the extra heat is used to change the water from a liquid to a gas.

To better understand the difference, consider a large iceberg and a cup of hot coffee.

  • An iceberg contains more heat because it contains a large amount of cold water, even though its temperature is low.
  • A cup of coffee has a higher temperature per unit time, it is hotter than an iceberg, but because of its smaller mass it contains less heat overall.

Mathematical representation

We can represent heat using a mathematical formula. Here is an important equation connecting heat and temperature:

Q = mcΔT

Where:

  • Q = heat energy (joules)
  • m = mass of the substance (in kilograms)
  • c = specific heat capacity (joule/kg°C)
  • ΔT = Change in temperature (°C)

This formula shows that heat depends on the amount of the substance, the specific heat capacity (a factor unique to each substance that shows how much heat it needs to produce a temperature change) and the temperature difference. Meanwhile, temperature itself is about a per-particle measurement.

Conclusion

In short, heat is a transferable energy form that arises due to temperature differences, while temperature is a measure of how this energy is distributed among particles in the form of kinetic energy. A deep understanding of these principles explains why large bodies of water can store enormous amounts of heat without much change in temperature and allows efficient thermal systems to be designed.

We use the concepts of heat and temperature every day, from heating our homes to cooling food in refrigerators and even explaining climate changes. Understanding these fundamental concepts is essential for many scientific fields, including physics, chemistry, and engineering.


Grade 10 → 3.1.1


U
username
0%
completed in Grade 10

← Prev (3.1)
heat and temperature
Next (3.1.2) →
Temperature scale

Comments 



Difference Between Heat and Temperature

https://www.physicsflow.com/g10/3.1.1?pfal=en