Question

Two cars with identical engines overheated. A mechanic opened the hood of one car and left the hood of the other car closed. This table shows how the temperature of each engine changed over 10 minutes.

Engine Initial temperature (°C) Final temperature (°C)

Engine in the car with the closed hood 105 98

Engine in the car with the open hood 109 95


The next time the mechanic works with an overheated engine, she wants the engine to cool off quickly. What should she do to maximize the rate of thermal energy transfer out of the engine?

Answers:

Leave the hood of the car closed.

Leave the hood of the car open.

Either the rate of thermal energy transfer is the same whether the hood is open or closed.

Answer 1

Leave the hood open
There is a greater rate of change in temperature in the car with the hood open than with the hood closed

Answer 2

Step-by-step explanation:

Removes excess heat from the engine. Maintains a constant engine temperature. Increases temperature of a cold engine quickly. Warms the passenger compartment.