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by Ron Kurtus

A total of 94 comments and questions have been sent in. They are listed according to date.

## List of next 10 letters

### Country

Fluids Looking for an interesting experiment MEXICO

Floating Weight of tub of water with person floating in it USA

Floating Is cooking oil more dense than water? USA

Floating Would a cannon ball sink? USA

Floating Why is lime used in burials? USA

Floating Would a steel ball sink to the bottom of the ocean? USA

Pressure Does temperature affect the speed water runs? USA

Floating Why do dead bodies float? Ethiopia

Next 10

First 10 letters

Topic: Floating

### Question

March 28, 2006

HI I AM LISA IN GRADE 8
I HAVE 4 QUISTOINS ABOUT DESPLACEMENT
1)CAN THE VOLUME BE DONE FOR FINDING THE DISPLACEMENT FOR EACH SUBSTANCE?
2)WHAT HAD TO BE DONE FOR FINDING THE DISPLACEMENT OF SUBSTANCE THAT FLOATWED?
3)WHY DO WE ALWASYS MEASURE THE MASS AND THE VOLUME BEFORE FINDING THE DISPLACEMENT OF EACH ITEM?
4)WHY DID SOME SUBSTANCES FLOAT WHILE OTHERS SANK IN WATER?
THANKS ALOT FOR ANSWRING IT.

10654

You can put an object in a full container of water and collect the water that runs over. The volume of that water will be how much was displaced. If the object sinks, the volume of the water will be the same as the volume of the object. If it floats, then it will be just what is under water.

## Adding boat to container of water

Topic: Floating

### Question

March 20, 2006

Assume that a large container is supported by a wooden frame designed to support the container's weight filled half full with water. Thus the frame must withstand ther weight of the container and water.

Float a 5 lb. toy boat, buoyancy and displacement will have no effect on the weight. But now sink the boat so that it rests on the bottom. Will this increase the weight and cause the support to collapse? Bear in mind that the container and water will continue to remain the same and the boat weighs 5 lbs. The support is onl able to carry the weight of the water and container.

10515

Since no water left the containter, if you add a 5 pound boat to the container of water, it will now weight 5 pounds more, whether the boat floats or not.

## Looking for an interesting experiment

Topic: Fluids

### Question

March 14, 2006

Well, I am coursing the college and I need a very interesting experiment o proyect about thermodinamic, its a homework, I am searching experiments in the net, but I dont find a interesting experiment for me, and I need your help!!!!!! Please!!!! Thanks a lot!!!!

Zulema - MEXICO

10442

Many students have made a thermos bottle. See the Reader Questions in:
http://www.school-for-champions.com/science/thermalinsulation.htm

An interesting experiment should be something that is interesting to you and that you are curious to find an explanation. Look at something you see related to thermodynamics and ask "What would happen if we changed...xxx?" That is the beginning of experiments.

## Weight of tub of water with person floating in it

Topic: Floating

### Question

February 25, 2006

If you place a tub of water on a scale and it weighs 1,000lbs., would the weight of that tub of water increase if you get in the tub of water and float. No water spills over the edge thus keeping the amound of water in the tub consistent.

David - USA

10228

The weight would be the sum of the person, tub and water, whether the person floated or not. The floating only has to do with the density of the object compared to the density of the water.

Of course, it water spilled out for an object that floated, then the weight would remain at 1000 lbs.

## Is cooking oil more dense than water?

Topic: Floating

### Question

February 19, 2006

hi I just wanted to comment on this article because I am doing a Density project related to this topic. I just wanted to ask, is cooking oil more dense than water and salty water?

Emily - USA

10154

Typcially, cooking oil will float in water, thus making it less dense. Salty water is more dense than pure water.

## Would a cannon ball sink?

Topic: Floating

### Question

February 9, 2006

Would a cannon ball actuall float or sink in water supposely an ocean? Why?

- USA

10013

If the cannon ball was made of lead or iron it would sink in the ocean, because it has a greater density than salt water.

## Why is lime used in burials?

Topic: Floating

### Question

December 15, 2005

Hello,

I'm trying to do some research online about lime. I'm trying to figure out how/why it's used to destroy the remains of a dead body? I've seen it on TV shows before, just curious how it works.

Thnx,

Michael - USA

9386

From what I've seen, lime was not used to destroy the remains. In Biblical times it was ceremonially unclean for a Jew to touch a tomb. This is why they were whitewashed with lime, so they could be easily seen and not accidentally touched. Also, during the time of the plague in Europe, bodies were buried in lime to mark them and avoid digging them up and spreading disease.

Diseased cows are buried with lime or quicklime to avoid spread of the disease.

## Would a steel ball sink to the bottom of the ocean?

Topic: Floating

### Question

December 2, 2005

Will a solid steel sphyere sink all the way to the bottom of the deepest part of the ocean? And does salt water play a part? Could there be cannon balls floating around in very deep water?

Stephen - USA

9238

Whether an object floats or sinks depends on its density and the density of the fluid. Although the density of water increases with depth in the ocean, I doubt if it would become greater than that of steel. Also note that the density of the steel ball would also increase from the water pressure at the ocean depths. Salt water is more dense than pure water, but it would not make a difference in this case.

## Does temperature affect the speed water runs?

Topic: Pressure

### Question

November 26, 2005

Please help- we need information on this question - Does temperature affect the speed at which water runs? Cannot find anything on this question. Report is due in 4 days......Kids they'll drive you nuts won't they? (8th grade project)
Thanks in advance for any assistance. Sincerely,

Gail - USA

9117

If the water pressure is constant, temperature should not be a factor in how fast water runs. But since water expands when heated, there may be greater pressure in a closed system, thus increasing the speed it runs.

## Why do dead bodies float?

Topic: Floating

### Question

November 21, 2005

Living bodies can't float on the surface of water without swimming but dead bodies can float without swimming. why?

yalew - Ethiopia

9037

Sometimes, due to air caught in the clothing, a body will float for several hours before sinking. A newly dead body will sink when placed in water, but then gases of decomposition build up in the chest and abdomen and the body will float to the surface. After a while the gas escapes and the corpse will sink again.

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