Q1. All the energy your finger gives to the water must be preserved. But as the circle travels, the circumference of the wave increases, so it gets harder and harder for the wave to travel since it has less energy per cm and soon it will be impossible to see. If the wave could travel in one line, the pulse would travel nearly forever.(Of course, it is only theoretical, and there would be friction to slow the wave down)

Q2. If the diver plunged in straight like a needle and didn't move at all by muscle power, he(or she) would refract. But since light no mass, it can change direction a lot more easily than we can.

Q3. If it isn't, the sound wave will travel from the bell to the bottom of the jar and out into the air.(Because the two substances are in contact, the wave can travel to and from each other.) So we would hear the bell and the experiment would be a failure.

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> To be done after reading chap1.3 and 2.1
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> 1. Before taking a bath, tap the water in your bathtub with your finger. Waves form. But there is something else about this wave. The amplitude decreases. The circles you made disappear after traveling a few centimeters. Why and how does that happen?
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> 2. If light refracts in a new medium, why shouldn't our bodies refract as we dive in to a swimming pool? What do you think?
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> 3. In the vaccum sound experiment(p.41) give an answer to the question, 'why do you think the bell is suspended?'>