Answer:
1) in metal object heat transfer through the conduction .In vacuum heat transfer through only radiation .
In only gaseous state or in liquid state the heat transfer through convection hence option D is correct
Answer:
The answer is: Convection occurs in the presence of a liquid or a gas
Explanation:
Convection is a process by which heat is transmitted, either between two liquid or gaseous substances, provided they are at different temperatures.
Heat transfer occurs when there is a temperature gradient between the two bodies that are in direct contact; then, the heat flow flows from the hottest body to the least hot body. Liquids and gases are considered fluids.
