Physics: Thermodynamics

What is the mathematical relationship between the Celsius and Kelvin temperature scales?

T(K) = T(°C) + 273.15

State the formula for the linear thermal expansion of a solid material.

ΔL = αL₀ΔT, where α is the coefficient of linear expansion, L₀ is the initial length, and ΔT is the change in temperature.

Define specific heat capacity (c) and provide its standard SI units.

Specific heat capacity is the amount of heat required to raise the temperature of 1 kg of a substance by 1 Kelvin. Its units are J/(kg·K).

According to the Stefan-Boltzmann Law, how does the power radiated by a blackbody scale with its absolute temperature?

The radiated power (P) is proportional to the fourth power of the absolute temperature (T⁴).

State the Kelvin-Planck formulation of the Second Law of Thermodynamics.

It is impossible to construct a heat engine that, operating in a cycle, produces no other effect than the extraction of heat from a single reservoir and the performance of an equivalent amount of work.

Express the First Law of Thermodynamics in terms of internal energy (ΔU), heat (Q), and work (W) done by the system.

ΔU = Q - W, where ΔU is the change in internal energy, Q is the heat added to the system, and W is the work done by the system.

Explain why the temperature of a pure substance remains constant during a phase change, such as boiling, even though heat is being added.

The added thermal energy (latent heat) is used to overcome intermolecular forces and change the potential energy of the particles rather than increasing their average kinetic energy.

Describe the microscopic mechanism of thermal conduction in metallic solids.

Conduction occurs through both the vibrations of the crystal lattice (phonons) and the kinetic energy transfer by high-speed 'free' electrons.

In a calorimetry experiment with no heat loss to the environment, what is the governing equation for two substances reaching thermal equilibrium?

Q_lost + Q_gained = 0, or m₁c₁ΔT₁ = -m₂c₂ΔT₂.

What is the difference between natural (free) convection and forced convection?

Natural convection is driven by buoyancy forces resulting from density gradients due to temperature differences; forced convection uses external means like fans or pumps to move the fluid.