place your palm at the top of the container. don't you feel hot? what do you understand from this?
Answers
Answer:
Submerge your right hand in the pot with cold water. How would you classify the temperature of the water—cold or very cold?
Put your left hand in the pot with warm water. How does this water feel?
After having you hands in the pots for about a minute or two, pay attention to the temperature of the water in each pot again. Does the cold water still feel as cold as it initially did? What about the warm water? If it feels differently, do you think the actual temperature of the water in the pots changed considerably during this short time or has your perception of the temperature changed?
Now, simultaneously remove your hands from the pots with ice-cold and warm water and place both hands in the pot with room-temperature water. How would you label the temperature of the water in the pot? Does it feel hot, warm, lukewarm, cold or very cold? If it is hard to say, pay attention to what you would say if you felt only with your right hand and what would you say if you felt only with your left hand? Do your hands agree or disagree about the temperature of the water?
Extra: Instead of using two hands, give your index finger a warm bath and your middle finger of the same hand a cold bath. The sensory signals created by the thermoreceptor in this test run along the same sensory nerve up your arm to your brain. Would you still be able to say one finger feels cold and the other finger feels warm? Would you still get confusing messages when after a minute, you put both fingers in water at room temperature? Now try with a fingertip touching an ice cube and a warm cloth at the same time. Are you still able to say that half of the tip is warm and the other half is cold? Are you still confused when you put the fingertip on a room-temperature object?
Extra: In this activity the water in the hot and cold pots are different temperatures. What if you put your hand in contact with objects that feel cold or warm but are at the same temperature, such as a metal door knob or pot and the carpet or a wool sweater? These objects are all at room temperature but they appear to be different in temperature because they conduct heat differently. Let your whole hands touch these objects. Do you still get confusing messages if, after awhile, you put your hands in contact with a third material, such as glass?