Question

7 in restaurants, red heat lamps are put above food to keep it warm. the lamp doesnt touch the food. the light shines down onto the food and warms it. which type of heat transfer would this be?
a. convection
b. radiation
c. conduction
d. reflection
8 which of the following best explains why the end of a spoon sticking out of a cup of hot water also gets hot just like the end of the spoon in the hot water?
a. the hot water causes a chemical reaction to take place.
b. the heat from the hot water is conducted through the spoon.
c. the heat from the hot water is convected through the spoon.
d. radiation from the sun warms the other end.

Explanation:

Question 7

Step1: Recall heat transfer methods

Convection is heat transfer through fluid (liquid or gas) movement. Conduction is heat transfer through direct contact. Radiation is heat transfer via electromagnetic waves (like light). Reflection is not a heat - transfer method (it's an optical property).
The red heat lamp emits light (electromagnetic waves) to warm the food without contact.

Question 8

Step1: Analyze each option

• Option a: Hot water and metal spoon (assuming it's a metal spoon) do not have a chemical reaction that causes heating.
• Option b: Convection is for fluids. The spoon is a solid.
• Option c: Metals are good conductors. Heat from the hot water (in contact with the spoon) is conducted through the spoon.
• Option d: The situation has nothing to do with the sun.

Answer:

1. b. radiation
2. c. The heat from the hot water is conducted through the spoon.