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All 9 questions. After you submit, each question shows the right answer and why. Back to the quick check
When you hold an ice cube, 'cold' flows from the ice into your hand.
A hot mug of cocoa with a lid on is left on the kitchen table. What happens to it over time?
What is a temperature of 25 °C on the Kelvin scale, in kelvins, to two decimal places?
How does heat from the Sun reach Earth across empty space?
How much heat, in kilojoules to one decimal place, is needed to warm 2.0 kg of water by 5.0 K? Take c = 4186 J/(kg·K).
A gas absorbs 500 J of heat and does 200 J of work pushing a piston. By how many joules does its internal energy change?
1200 J of heat flows reversibly into a large reservoir held at 300 K. What is the reservoir's entropy change, in J/K?
What is the maximum possible efficiency, as a percentage, of a heat engine working between reservoirs at 600 K and 300 K?
Show that if heat could flow spontaneously from cold to hot (violating the Clausius statement), you could build an engine that converts heat from a single reservoir entirely into work, violating the Kelvin statement.
