air occupies space
When a cup of water is twirled at 360 degrees, the centripetal force created by the motion of the cup keeps the water inside. This force acts inward, preventing the water from spilling out even when inverted. As long as the centripetal force is greater than the force of gravity pulling the water downward, it will remain in the cup.
The easiest method is to weigh the water ... weigh the cup empty and full and take the difference ... and then divide the weight by the acceleration of gravity. Since the acceleration of gravity is well known on Earth, that method is accurate and easy, but it wouldn't work in another place where you didn't already know the value of that quantity.
Of course a paper cup would be more flexible. Nails are hard to bend.
One simple method is to place the paper cup inside a second paper cup. The air gap between the cups provides a fair amount of insulation and slows heat loss.
This is because you are not changing the mass of the water, there are still the same amount of molecules in the cup, although more energized they still occupy [relatively] the same amount of room. I say relatively, because the molecules are slightly more spaces, due to the energy obtained with heat.
A paper cup typically does not keep water hotter than a plastic cup. Paper is a poor insulator compared to plastic, so heat is more likely to escape from a paper cup, leading to faster cooling of the water inside.
The boiling point of water is 100 degrees. However, the point at which paper burns is much higher than 100 degrees. When you boil water in a paper cup, all of the heat is transferred to the water, not the cup. When the water starts to boil, the paper stays unburnt. After the water has boiled through, there should be a small black mark on the base of the cup which can be easily removed.
A paper cup full of water doesn't catch on fire because water absorbs heat, preventing the paper from reaching its ignition temperature. As the cup is exposed to a heat source, the water absorbs the heat, keeping the paper cool enough to avoid combustion. Additionally, the water acts as a barrier, preventing the paper from direct contact with the flame. Thus, the presence of water effectively protects the paper cup from catching fire.
A paper cup can be used to boil water by filling it with water and placing it directly over a heat source such as a stove or campfire. The water will boil due to the heat transfer from the flame to the paper cup, causing the water to reach its boiling point. The paper will char and may eventually catch fire, so this method should be done with caution.
the paper cup cannot become appreciably hotter than the water it contains
The boiling point of water is just 100 deg celcius. But the ignition temperature for paper would be higher than 200 deg celcius. So when paper cup filled with water it cannot attain temperature higher than 100 deg. Hence no burning becomes possible
A metal cup will generally keep hot water hotter for longer compared to a paper cup. Metal is a better insulator than paper, so it helps to retain heat more effectively.
The number of paper clips that can fit in a cup of soapy water will depend on the size of the cup, the size of the paper clips, and how the clips are arranged. It is difficult to provide an exact number without specific details.
Plastic is an insulator. but most of the paper is not insulated, because the paper in general contains water, although the content is very low, but enough to pass current, but there also is a special insulation paper, that is on the special purpose. so in dry conditions, and the cup has no water, a plastic cup is a better insulator than a paper cup.
1/2 a cup of water
paper
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