Page 33 - Utah Science Textbook
P. 33
REAL LIFE SCIENCE To better understand density, think about a bowling ball and a volleyball. The bowling
ball feels heavy. It is solid all the way through. It contains a lot of tightly packed particles
Today you can measure of matter. In contrast, the volleyball feels light. It is full of air. It contains fewer, more
the mass of the air in a widely spaced particles of matter. Both balls have about the same volume, but the bowling
basketball. Measure the ball has a much greater mass. Its matter is denser. Here is a great video on the density of
mass of the basketball liquids.
when deflated. Then http://www.youtube.com/watch?v=B3kodeQnQvU (4:00)
inflate the ball 10 psi and
measure the mass again.
The difference in the
masses will be the mass
of the air in the ball!
According to the table above:
1. Will any substances listed float on water?
2. What will float on mercury?
3. Will a lead fishing weight float on liquid mercury?
4. What would happen to the rock if you threw it into the mercury?
If you were asked if a lead fishing weight floats you would quickly answer no. But the
correct answer depends of what you are trying to float it on. Obviously, the lead fishing
weight would sink in water, but what about other substances? Liquid mercury has a
density of 13.55 and lead has a density of 11.35. Since the density of lead is lower than the
density of mercury the lead would float on the mercury.
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ball feels heavy. It is solid all the way through. It contains a lot of tightly packed particles
Today you can measure of matter. In contrast, the volleyball feels light. It is full of air. It contains fewer, more
the mass of the air in a widely spaced particles of matter. Both balls have about the same volume, but the bowling
basketball. Measure the ball has a much greater mass. Its matter is denser. Here is a great video on the density of
mass of the basketball liquids.
when deflated. Then http://www.youtube.com/watch?v=B3kodeQnQvU (4:00)
inflate the ball 10 psi and
measure the mass again.
The difference in the
masses will be the mass
of the air in the ball!
According to the table above:
1. Will any substances listed float on water?
2. What will float on mercury?
3. Will a lead fishing weight float on liquid mercury?
4. What would happen to the rock if you threw it into the mercury?
If you were asked if a lead fishing weight floats you would quickly answer no. But the
correct answer depends of what you are trying to float it on. Obviously, the lead fishing
weight would sink in water, but what about other substances? Liquid mercury has a
density of 13.55 and lead has a density of 11.35. Since the density of lead is lower than the
density of mercury the lead would float on the mercury.
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