Topic B.

How is temperature related to kinetic energy?

Temperature is proportional to the average kinetic energy of the particles in a substance.

What is specific heat capacity?

The amount of energy required to raise the temperature of 1 kg of a substance by 1 K.

What is Q in thermodynamics?

Q represents thermal energy (heat) transferred to or from a system.

What is latent heat of vaporisation?

The energy required to change 1 kg of a substance from liquid to gas at constant temperature.

What is latent heat of fusion?

The energy required to change 1 kg of a substance from solid to liquid at constant temperature.

How do latent heat of fusion and vaporisation differ? Which is higher?

Fusion is for solid to liquid, vaporisation is for liquid to gas. Latent heat of vaporisation is higher because gas molecules require more energy to separate.

What is conduction?

Transfer of heat through direct contact between particles in a solid.

What is convection?

Transfer of heat by movement of fluid due to density differences.

What is radiation?

Transfer of heat via electromagnetic waves, requiring no medium.

What does n represent in PV = nRT?

The number of moles of gas.

What is the alternative formula for kinetic energy in thermodynamics?

KE = (3/2) k_B T for a single molecule or KE = (3/2) nRT for a gas.

What is the greenhouse effect?

The trapping of heat in Earth’s atmosphere by greenhouse gases, warming the planet.

What is emissivity?

A measure of how effectively a surface emits thermal radiation.

What is albedo?

The fraction of incident sunlight that is reflected by a surface.

What is the solar constant?

The amount of solar energy per unit area received at Earth's upper atmosphere (1361 W/m²).

What are the main greenhouse gases?

CO₂, CH₄, H₂O vapour, N₂O, and CFCs.

What is the formula for the solar constant?

S = L / (4π d²)

What is incoming radiative power?

The power per unit area received from the Sun. Formula: S / 4

What is the enhanced greenhouse effect?

The increase in Earth's temperature due to human-induced greenhouse gas emissions.

What does the first law of thermodynamics state?

Energy cannot be created or destroyed; ΔU = Q - W.

What is U in thermodynamics?

Internal energy of a system.

What is a closed system?

A system that exchanges energy but not matter with its surroundings.

What is an isolated system?

A system that exchanges neither energy nor matter with its surroundings.

What is work done by a closed system?

Work is positive when the system does work on the surroundings.

What is work done to a closed system?

Work is negative when the surroundings do work on the system.

What are the formulas for internal energy?

U = (3/2) nRT or U = (3/2) Nk_B T.

What does isovolumetric mean for work?

Volume is constant, so no work is done.

What does isobaric mean for work?

Pressure is constant, so work is done as volume changes: W = P ΔV.

What does isothermal mean for work?

Temperature is constant, so ΔU = 0 and Q = W.

What does adiabatic mean for work?

No heat exchange, so ΔU = -W.

What is the efficiency formula for a heat engine?

η = (Q_H - Q_C) / Q_H.

What does the second law of thermodynamics state?

Entropy always increases in a closed system.

What is the microscopic entropy formula?

S = k_B ln Ω, where Ω is the number of microstates.

What is the macroscopic entropy formula?

ΔS = Q / T for reversible processes.

What does the second law mean in terms of entropy?

The total entropy of an isolated system never decreases.

What is current?

The rate of flow of charge, I = Q / t.

What is potential difference?

The work done per unit charge to move a charge between two points.

What is resistance?

Opposition to the flow of current, R = V / I.

What is EMF?

Electromotive force, the energy provided per unit charge by a source.

How do the dimensions of the confuctor affect resistance?

Shorter wires will have less resistance

Longer wires will have moreresistance

Thicker wires will have less resistance

Thinner wires will have more resistance

Why should the voltimeter be put outsidethe cicuit?

Because it has infinite resistance soif its inside the charges cannot flow

What is the graph of pressure vs. volume for a gas at constant temperature?

Hyperbolic ().

What is the graph of pressure vs. temperature for a gas at constant volume?

Linear ().

What is the graph of volume vs. temperature for a gas at constant pressure?

Linear ().

What is the graph of average kinetic energy vs. temperature?

Linear ().

What does a temperature vs. time graph look like during phase transitions?

Plateaus occur at phase transitions (melting and boiling).

What is the graph of pressure vs. volume for an ideal gas during an isothermal process?

Hyperbolic ().

What is the graph of temperature vs. heat energy added for a substance?

Linear, with the slope equal to