Thermal Energy Transfer And Equilibrium
A sealed thermos flask has a vacuum between its inner and outer walls, and the inner surfaces are coated with a reflective material. Which statement best explains why the vacuum alone does not completely eliminate thermal energy loss from the hot liquid inside?
A student places a copper rod at 90 °C into a beaker of water at 20 °C. After a long time, the rod and the water are both at 35 °C. Which statement correctly describes the state of the system at 35 °C?
A large block of iron at 300 °C is placed in thermal contact with a small cup of water at 25 °C. A student predicts that the final equilibrium temperature will be exactly 162.5 °C — the arithmetic mean of the two initial temperatures. Which reasoning best explains why this prediction is likely incorrect?
On a cold winter morning, a student touches a metal doorknob and a wooden door at the same time. Both objects are at the same temperature, yet the metal feels much colder. Which explanation is correct?
A scientist places two identical aluminium blocks — one at 400 K and the other at 200 K — in thermal contact inside a perfectly insulated container. Considering a single collision between one atom from the hot block and one atom from the cold block, which statement is correct?
A warm glass of water is placed inside a refrigerator. Which description correctly identifies the thermal processes involved as the water cools?
A satellite orbits Earth in the vacuum of space. The side of the satellite facing the Sun reaches a much higher temperature than the side facing away. By which thermal process does the satellite receive energy from the Sun?
A physicist observes two gas samples separated by a thin metal wall. Sample X is at 600 K and Sample Y is at 300 K. After the samples reach thermal equilibrium, the physicist examines the microscopic behaviour of the gas molecules. Which observation is consistent with thermal equilibrium?
In a coastal town, a student notices that during the daytime a breeze blows from the sea toward the land. At night, the breeze reverses direction, blowing from the land toward the sea. Which thermal process is primarily responsible for driving these breezes, and what causes the reversal?
Two systems are in thermal contact. System P has a large mass and high specific heat capacity; System Q has a small mass and low specific heat capacity. Both start at different temperatures. As they approach thermal equilibrium, which statement correctly describes the temperature changes?
A student fills a dark-coloured metal container and a shiny silver container with equal volumes of boiling water and leaves both in the same room. After 30 minutes, the water in the dark container has cooled more than the water in the shiny container. Which explanation correctly accounts for this observation?
Consider a system where a warm iron sphere is dropped into a large, insulated tank of cool water. The iron and water eventually reach thermal equilibrium. A student claims: “At equilibrium, the iron transferred all of its thermal energy to the water.” Determine whether this claim is correct and identify the flaw in the reasoning if it is incorrect.
An astronaut on a spacewalk in Earth’s orbit accidentally releases a metal wrench. The wrench floats in the vacuum of space, exposed to direct sunlight on one side and deep space on the other. After a long time, the wrench reaches a stable temperature. Which statement best explains why the wrench reaches a stable temperature rather than continuing to heat up indefinitely?