Question: If a thermal camera records the entire process at a constant frame rate, what feature is most likely to appear in the liquid’s temperature field at the instant the transition occurs?
A. A rapid temperature rise first appears near the contact point, then the “hot zone” spreads outward, and over tens of seconds the overall temperature slowly falls back.
B. A rapid cooling appears first and then spreads outward.
C. The temperature remains essentially unchanged.
D. Only the cup wall warms while the liquid’s temperature stays unchanged.
Clues:
1. The left image shows a clear, transparent liquid in a glass.
2. The right image shows a white, crystalline, solid-like substance forming inside the same glass of liquid.
3. A finger is shown touching the surface of the liquid in the right image.
4. The formation of the white substance originates from the point where the finger touches the liquid surface.
5. The white substance appears to be spreading downwards and outwards from the point of contact.
Answer: A
Category: Physics