5 Minute STEM Activity 7: Is it warm, or is it cold?

Today's 5 minute activity is one of the very simplest, but most effective. Our bodies and brains are incredibly complicated and clever, and most of the time they work together really well, but it is possible to confuse our brains and make it appear that something isn't what it seems.

Is it warm, or is it cold?
Confusing Your Brain.

EQUIPMENT:
Your hands
1 bowl cold water - from the cold tap
1 bowl lukewarm water - 2/3 cold and 1/3 hot
1 bowl warm water - comfortably warm and toasty

Instructions:
1. Place the 3 bowls on the table in order of heat - cold, lukewarm, warm.
2. Put one hand into the cold water
3. Put one hand into the warm water
4. Wait 30 seconds

4. Move one hand into the middle bowl, it doesn't matter which hand you choose.

5.  Is the water in the middle bowl warm or cold?

6. Now put the other hand into the middle bowl too. What temperature is the water in the middle bowl? Occasionally you can see the magic when a child gets a result from an experiment. I think we captured it here...

What happens to your hands? Which is cold now and which is warm? Why do you think this happens?

Your hands register a big change in temperature and your brain has to try and work it out. Because you make dramatic, sudden changes, it's easy to spot how long it takes before your brain catches up.

If you enjoyed that, you can try creating the same effect if you stroke something rough (like carpet or towel) and something smooth (something shiny like rubber or plastic) and then stroke something neither rough nor smooth (like denim jeans).

You can find the other 5 Minute STEM Activities so far at the links below, and I'll keep doing some more through the Summer holidays.

Fish In The Tank
The Floating Arm Trick
The 5cm World Challenge
What Is Gluten?
How To Step Through A Hole In A Postcard

Turn Black To White