Termodinâmica e calorimetria · AP Physics 2 Unit 2 (Thermodynamics)
Simulador da lei dos gases ideais e diagramas p-V
Simulador da lei dos gases ideais e transformações termodinâmicas: p·V = n·R·T e diagramas p-V
- No navegador
- Sem cadastro
- Dedução ao vivo
- Modo projetor
- Folha de exercícios A4
Janela de simulação 3D● 60 FPS
Variáveis de controle do experimento
kPa
L
K
Deduções e métricas em tempo real
Produto nR
--
Trabalho de fronteira W
--
Variação de energia interna ΔU
--
Calor trocado Q
--
Dedução de fórmulas em tempo real
Fórmula fundamental:
--Substituição de valores:
--Estado físico: --
Exemplos clássicos e armadilhas de exame
Worked Problem
Problema: Gas at p1=100kPa, V1=2.0L, T1=300K is compressed isothermally to 1.0L. Find final pressure.
Derivação passo a passo:
- Isothermal Boyle's Law: p1*V1 = p2*V2 => p2 = (100kPa * 2.0L) / 1.0L = 200 kPa.
Worked Problem
Problema: Car tire is 200kPa at -3°C (270K). Summer heat raises air inside to 54°C (327K) at constant volume. Find new pressure.
Derivação passo a passo:
- Charles's Law: p2 = p1 * (T2/T1) = 200kPa * (327/270) ≈ 242 kPa.
Folha de investigação em aula e exercícios
Q1. Variant 1: Why must thermodynamic calculations use Kelvin rather than Celsius?
Answer Key: Must use absolute Kelvin (K = °C + 273.15)! State laws establish proportionalities anchored at absolute zero (0K); Celsius offsets break linearity.
Q2. Variant 2: State the First Law of Thermodynamics ΔU = W + Q and clarify sign conventions.
Answer Key: W > 0: work done ON system; W < 0: work done BY system. Q > 0: heat absorbed; Q < 0: heat rejected. ΔU > 0: internal energy increases.
Q3. Variant 3: In adiabatic expansion (Q = 0), does gas temperature rise or drop? Explain.
Answer Key: Temperature drops! By ΔU = W + Q with Q=0, expansion work by gas (W < 0) reduces internal energy ΔU < 0, cooling the gas.
Perguntas frequentes e erros comuns
Under what conditions do real gases behave like ideal gases?
At high temperatures and low pressures! Molecular volumes become negligible relative to total container volume, and intermolecular forces vanish.
When pumping a bicycle tire, why does the lower pump cylinder get hot?
Primarily adiabatic compression work! Forcefully compressing air does mechanical work on it, spiking gas temperature. Friction is negligible in comparison.
Why does a misty cloud form at the bottle neck when popping a champagne cork?
Rapid adiabatic expansion work drops gas temperature by dozens of degrees within milliseconds, instantly condensing surrounding water vapor into mist.
What is Absolute Zero (0K = -273.15°C)? Can experimentalists reach it?
Theoretical ground state where thermal kinetic motion drops to quantum zero-point energy. The Third Law of Thermodynamics proves it can never be reached.