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Why can many drops of water be put on the surface of a penny without spilling over the sides?
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Drops on a penny?
Cohesion and Surface Tension
Why does water stay on a penny?
Surface tension allows water to form a large drop on a penny before popping and spilling off.
How can so many drops of water fit on a penny?
It all depends on if you drop the water fast or if you drop it slow. Ideally, everyone performing the experiment would include the following: - distilled waterThere are a lot of factors involved. The cohesion and adhesion ('stickiness') of water molecules can be effected by things like oils (on surface pennies from peoples' skin) and other contaminates on the penny. The size of the dropper or pipette will determine the size of each water droplet - the larger the drop, the fewer number of drops will fit on the penny. The manner in which the water is added to the penny is also a factor. Water has a cohesive nature (the molecules are kind of like magnets and are attracted to one another). Therefore, if the drop from the pipette is allowed to touch the water already on the surface of the penny, the water can be 'pulled' out of the dropper. When this happens, the size (volume) of the drop is not always the same - it could be a very small amount (which will result in a very large number of drops), or a large amount. Soap causes the cohesiveness ('stickiness') of the water molecules to decrease so they are not as strongly attracted to each other. Because of this, when soap is added to the water the number of drops that can be placed on the penny will decrease. The water molecules can't 'stick' together as well, so the water on top of the penny spills off sooner than it would with non-soapy water. Ideally, everyone performing the experiment would include the following: - distilled water (to start with) - same type/size of calibrated dropper/pipette - same date of penny - penny cleaned as thoroughly as possible using same cleaning procedure - same 'dropping' procedure
What variables may play a factor in the amount of drops the penny hold?
Several factors can come into play here.The size of the dropsHow fast the liquid is being droppedWhat type of liquid is being usedThe temperature of the liquidThe termperature of the pennyIf the penny was clean or dirtyThe height the drop falls fromAny of these things can have an effect an expansion of the liquid, surface tension, and splash.
What keeps water on a penny?
Surface tension keeps water on a penny even when it goes over the surface of the penny and you think it would spill over the edge due to gravity. I believe surface density is accomplished due to the fact that the hydrogen bonds, for that scale, is stronger than the force of gravity. For more information look at the Related Links below.
Drops on a penny?
Cohesion and Surface Tension
Why does water stay on a penny?
Surface tension allows water to form a large drop on a penny before popping and spilling off.
How surface tension behaves?
for example, if drops of water are placed on the top of a penny, the surface tension is going to hold the drops on top of the penny. when the penny can hold no more, it will all overflow. make sense?
How many drops of water can fit on a penny research paper?
Alot of drops fit because if you keep the surface tension from moving then you could put as much drops as you can.] ==If you put a penny on a flat surface and keep its tension and keep the penny from moving you can put as much drops as you can till it leaks off. You cant put as much as you want cause the penny will overflow. its not a big object?
When was When the Penny Drops created?
When the Penny Drops was created in 2010.
How many drops of water can a penny hold on its surface?
Water has a surface tension. When dropping water on a penny, people usually underestimate how much water the surface of a penny can hold. The surface tension of water is strong on a smaller surface, and when dropping water on the surface of a penny, towards 20 drops the water on the penny will look like it is bulging out a lot. It really depends, depending on which side of the penny you are using, it ranges from 6 to even 34 drops using a simple eyedropper. Because eyedroppers do not produce the exact same size of drops every time, the result is not very accurate. To be even more accurate, scientists use accurate distributing machines and a very new penny to determine how many drops of water it can hold without vibrations. There could be certain amounts of grime and dirt on a penny, depending on how old it is, which can affect how much water can be put onto it. Different types of water can also change how much a penny can hold. Tap water has certain amounts of chemicals in it, and that could also affect the weight and surface tension of the water on the penny. The height of which the water comes off from matters too, the more force of the water that comes down, the more likely the water on the penny is to splash and spill. The place the water lands on also has an effect on it. To be even more accurate, light has a mass. If light shines directly at the water on a penny, it could push it a tiny bit. This change is impossible to see, and it has basically no effect on the penny or water at all whatsoever. Remember, all tests may not be 100% accurate, and there may always be a chance that there is a better way to make a penny hold more droplets of water than the presumed "most advanced and accurate" way.
What is the control on the penny water drops experiments?
In this experiment, the control group would be the penny! The independent variable is the substance/water on the penny, and the dependent is how many drops the penny takes.
Does the temperature affect number of drops needed for surface tension on a penny?
the chemistry of cohesion
How many drops of water can fit on a US penny?
One large drop of rain, or as many as 20 average-sized drops of water from an eyedropper, given maximum surface tension. As many as 35 of the smallest drops can hold together atop the coin.
Why does a penny hold more water drops than drops of oil?
Small drops of liquids tend to be spherical because of their surfacetension. Surface tension is the result of intermolecular attractingforces. When you put a small drop of a liquid on a solid surface, theinermolecular forces of the solid surface will tend to attract the liquidmolecules. Depending on the magnitude of the different forces, the solidsurface will present certain degree of 'wettability'. If you compare howa drop of water sits on a clean penny and on a penny that you rubbedwith your fingers, you'll notice that the drops contact angle differ.The drop on the clean penny will cover more contact area (more wettablesurface) than the drop on the 'oily' penny (less wettable surface). Oilreppels water because the intermolecular forces between the water andoil molecules are very weak compared to the intermolecular forces betweensimilar molecules.Now, water intermolecular forces are paricularly strong, and so the dropof water on the penny will resist more than the oil molecules to be spreadedon the surface of the penny. Oil drops tend to wet more the surface of thepenny and will tend to occupy more area. And so you'l get fewer oil dropson the penny's surface.
How many drops can you hold on a penny list one uncontrolled variable?
The penny's state of corrosion.
Science fair project topics?
how many drops of water can a penny hold? topic: crazy penny........
