Thermodynamics Flashcards
7 cards from real Ramsay Test practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Thermodynamics flashcards as text
What does a Carnot cycle represent in thermodynamics?
Answer: The most efficient possible heat engine
The Carnot cycle defines the maximum theoretical efficiency between two temperatures.
As the temperature of a gas increases at constant volume, what happens to its pressure?
Answer: It increases
By Gay-Lussac's law, pressure rises proportionally with temperature at fixed volume.
What is the term for heat that changes a substance's temperature without changing its phase?
Answer: Sensible heat
Sensible heat produces a measurable temperature change you can sense.
A heat engine's thermal efficiency is the ratio of work output to what?
Answer: Heat input
Thermal efficiency equals net work output divided by the heat energy supplied.
What process describes a substance changing directly from solid to gas?
Answer: Sublimation
Sublimation is the direct transition from solid to vapor without becoming liquid.
On the Kelvin scale, what value corresponds to absolute zero?
Answer: 0 K
Absolute zero is 0 kelvin, the point of minimum molecular motion.
Why is a vacuum used between the walls of a thermos flask?
Answer: To reduce conduction and convection
A vacuum removes the medium needed for conduction and convection, limiting heat loss.