Darrel conducted an experiment with the following procedure: Fill two cups with ice water. Place an uninflated balloon snuggly onto your left index finger. Blow a little air into an identical balloon, and place it onto your right index finger. Place both fingers into the cups of ice water. Darrel noticed that his right finger felt warmer in the ice water than did his left finger. Which of the following does the experiment show?

A. Air is a good radiator of heat.

B. Air is a good insulator of heat.

C. Air is a good conductor of heat.

D. Air is a good convector of heat.

B. Air is a good insulator of heat.

Explanation:

The right index finger felt warmer than left index finger because air is good insulator of heat. This is because for heat transfer via conduction, the molecules vibrate and collide with neighboring molecules and transfer energy. Since, the air molecules are very loosely packed, conduction of heat is very slow and difficult.

As we know, heat transfers from hotter body to colder body, the heat transferred from left index finger through solid balloon piece to ice water. But, in right index finger had air filled balloon which is not a good conductor of heat and hence, the finger was warmer.

C. Air is a good conductor of heat