Concept:Newton's Law of Cooling states that the rate of change of temperature of an object is proportional to the temperature difference between the object and its surroundings.
It applies only to cooling or heating without phase change.
Explanation:Evaluate each case:
Case 1: Ice melting in water involves a phase change (solid to liquid) and absorption of latent heat.
Newton's Law does not apply because it deals with temperature change, not phase transformation.
Case 2: Water boiling openly is a phase change (liquid to gas) at constant temperature.
It involves latent heat of vaporization, not simple cooling or heating.
Case 3: A metal rod heated in a furnace experiences high temperatures and multiple heat transfer mechanisms.
Newton's Law is typically valid for moderate temperature differences and simple cooling without drastic environmental changes.
It is not directly applicable here.
Case 4: A cup of coffee cooling on a table is a classic example.
Hot coffee transfers heat to the surrounding air, and the cooling rate depends on the temperature difference between coffee and air.
This fits Newton's Law.
Therefore, only case 4 satisfies the conditions.
Answer:B. 4 only