Great question, Lyana!  There are several different ways you can produce heat:

1.       You can focus the sun’s rays using a magnifying glass, but watch where you point the focused beam of light because it can set things on fire!

2.       You can use friction—by rubbing two objects together, the friction between them creates heat.  You can prove this to yourself just by rubbing your hands together; as you rub them together they will begin to feel warm.

3.       You can use chemicals to create heat.  As some chemicals dissolve in water, they give off heat.  This is called an exothermic reaction.  One such chemical is magnesium sulfate (MgSO4), which you can purchase inexpensively on the internet (http://www.ebay.com/itm/like/280605941369?lpid=82)

I would suggest you use the chemical approach, and ask your parents to help you purchase some MgSO4, and dissolve about ½ cup of it in 1-2 cups of water in a plastic bottle.  Shake the bottle well to dissolve the MgSO4.  Have your teacher and classmates touch the bottle, and feel how warm it gets (be careful—it could get very warm!).


For more information about exothermic chemical reactions, please visit http://en.wikipedia.org/wiki/Exothermic_reaction

Thanks for your question, Robin!

            When you look in a mirror, you see a reflection of yourself.  Naturally, you expect that image of yourself to appear as it would to anyone standing in front of you looking at you.  But that’s not exactly what happens!  If you stand in front of a mirror wearing a shirt with letters on it, those letters will appear reversed in the mirror. 

The reason this happens is because the mirror does not simply present an image of you, it presents a reflection of you.   That is, when you stand in front of the mirror light is traveling away from you in a straight line, hitting the mirror, and bouncing back to you.  The light bouncing back creates the image you actually see in the mirror.

            Think of it like this: imagine you are bouncing a ball off the mirror.  If you throw the ball straight at the mirror with your right hand, it will bounce back to your right hand.  If the ball bounces off your head toward the mirror, it will bounce back at your head!  This is exactly what the light is doing; traveling away from you, and bouncing off the mirror.  This bouncing light is what you see in the mirror—your reflection. 

            The way this bounced light presents an image of you is a bit like the way a piece of paper presents an image of a rubber stamp.  Take a look at the bottom of a rubber stamp: if there are words on it, they appear reversed.  When you dip the stamp in ink, and press it on paper, the words appear as they should.  It’s the same if the stamp is a picture—the picture on the stamp itself is reversed compared to the image on the paper.  The paper is like the mirror, and the ink is like the light bouncing off the mirror—it is creating an image of you that is the reverse of what you actually look like.