The man is holding the suitcase at the same height above the surface of earth. So the gravitation potential energy remains the same.
<span>work done is force * displacement = weight * 0 = 0</span>
Complete Question
An isolated charged soap bubble of radius R0 = 7.45 cm is at a potential of V0=307.0 volts. V0=307.0 volts. If the bubble shrinks to a radius that is 19.0%19.0% of the initial radius, by how much does its electrostatic potential energy ????U change? Assume that the charge on the bubble is spread evenly over the surface, and that the total charge on the bubble r
Answer:
The difference is 
Explanation:
From the question we are told that
The radius of the soap bubble is 
The potential of the soap bubble is 
The new radius of the soap bubble is 
The initial electric potential is mathematically represented as
The final electric potential is mathematically represented as
The initial potential is mathematically represented as

The final potential is mathematically represented as

Now

substituting values

=> 
So
Therefore
where k is the coulomb's constant with value 
substituting values

C) because you could get hurt if certain items fall in it and you are in water
B. Fusion requires very high pressure and temperature.
Explanation:
Nuclear fusion is the combination of atomic nuclei into larger ones with the release of a large amount of energy.
Nuclear fission is the decay process in which a heavy nuclide is bombarded with with neutrons.
- Both processes release a huge amount of energy.
- But fusion produces far more energy.
- The reason why nuclear fusion is not in use is because of the high pressure and temperature needed start it.
- The activation energy is high and the energy barrier is very great.
- Only the core of the sun naturally favors fusion
learn more:
transmutation brainly.com/question/3433940
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Answer:
one of the reasons is that it wets the glass thermometer it also doesn't detect slight changes in temperature of the atmosphere it has a high boiling point I don't know the rest