Title: InkPhysics / Thermal physics
On every note of this deck, unless a note says otherwise:
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Front: DEFINITION
Define: Specific heat capacity.
Back: The energy needed to raise the temperature of one kilogram of a substance by one kelvin without a change of state.

Front: RECALL
State the purpose of the two flow rates in the continuous-flow method.
Back: With the same inlet and outlet temperatures the heat loss is the same in both runs, so subtracting the two eliminates it.

Front: DEFINITION
Define: Brownian motion.
Back: The continual random motion of visible particles, such as smoke grains, suspended in a fluid.

Front: DEFINITION
Define: Describe the smoke cell demonstration of Brownian motion.
Back: Smoke from a smouldering taper is sealed in a small glass cell, lit from the side and viewed through a microscope. Each smoke particle shows as a bright speck jerking about randomly and independently of the rest.

Front: RECALL
State absolute zero in degrees Celsius.
Back: Absolute zero, 0 K, is −273 °C.

Front: SPOT THE ERROR
Say what is wrong with this claim: Zero degrees means zero heat.
Back: 0 °C is an arbitrary zero, the freezing point of water; molecules there still move rapidly. Particles have minimum internal energy at absolute zero, 0 K or −273 °C.

Front: DEFINITION
Define: Root mean square speed.
Back: The square root of the mean of the squares of the molecular speeds.

Front: DEFINITION
Define: Describe the arrangement and motion of particles in a solid.
Back: Particles are close together in a regular repeating arrangement, held by strong forces, each vibrating about a fixed position and unable to change places with its neighbours.

Front: EQUATION · NOT ON THE DATA SHEET
Work done by a gas at constant pressure:
W = ?\(W = \, ?\)W = ?
Back: W = pΔV\(W = p\Delta V\)W = pΔV

Front: SPOT THE ERROR
Say what is wrong with this claim: Air pressure comes from air's weight pressing down.
Back: Gas pressure is not weight acting downwards. It comes from molecules colliding with surfaces, each impact changing momentum and exerting a force, so pressure acts equally in all directions.

Front: RECALL
State the evidence from Brownian motion.
Back: Brownian motion is evidence that a fluid consists of molecules in rapid random motion, bombarding the suspended particles unevenly.

Front: SPOT THE ERROR
Say what is wrong with this claim: Heat and temperature are the same thing.
Back: They are different quantities. Temperature tracks the average random kinetic energy of the particles, exactly proportional to it for an ideal gas; heat is energy transferred between bodies because of a temperature difference.

Front: DEFINITION
Define: Charles's law.
Back: At constant pressure, the volume of a fixed mass of gas is proportional to its absolute temperature.

Front: DEFINITION
Define: Absolute zero.
Back: The temperature at which the particles of a substance have minimum internal energy.

Front: RECALL
State the two ways to increase the internal energy of a system.
Back: Heating it, or doing work on it.

Front: DEFINITION
Define: Describe the arrangement and motion of particles in a liquid.
Back: Particles are close together, as in a solid, but disordered beyond the nearest few neighbours, and they slide past one another while staying in contact.

Front: RECALL
Explain why temperature is constant during a change of state.
Back: The energy supplied increases the potential energy of the particles, not their kinetic energy.

Front: DEFINITION
Define: Internal energy.
Back: The sum of the randomly distributed kinetic and potential energies of the particles in a body.

Front: DEFINITION
Define: Boyle's law.
Back: At constant temperature, the pressure of a fixed mass of gas is inversely proportional to its volume.

Front: DEFINITION
Define: Specific latent heat.
Back: The energy needed to change the state of one kilogram of a substance without a change of temperature.

Front: DEFINITION
Define: The Avogadro constant.
Back: The number of particles in one mole: 6.02 × 10^23 mol^−1.

Front: RECALL
State the internal energy of an ideal gas.
Back: Entirely kinetic: with no intermolecular forces there is no potential-energy contribution.

Front: DEFINITION
Define: Ideal gas.
Back: A gas that obeys pV ∝ T at all pressures, where T is the thermodynamic temperature.

Front: RECALL
State what determines the average kinetic energy of a gas molecule.
Back: Only the absolute temperature: mean translational KE = (3/2)kT, the same for every ideal gas.

Front: DEFINITION
Define: Describe the arrangement and motion of particles in a gas.
Back: Particles are far apart, roughly ten times the spacing in a liquid, in no arrangement at all, moving rapidly in random straight lines with negligible forces between collisions.