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6

Yes the core will warm gradually. Heat transfer in a solid is conduction. Ice has a known thermal conductivity and will have a linear temperature profile from all paths from surface to center. There will be concentric rings of constant temperature at all times. It would be impossible to warm just the surface and not warm up the molecules next to the ...


3

In principle, no, you cannot make a Dyson sphere which is indistinguishable from the CMB. The reason is fairly simple. Let's start with a blackbody DS which encloses nothing at all, and is so far from any nearby stars that no noticeable radiation reaches it. Since it is surrounded by CMB with an effective temperature of 2.75 K, it will reach an equilibrium ...


2

The energy gets converted into the form of heat and sound. In this way the energy is conserved.


2

I am sorry to disappoint you, but there is no such formula that you can just apply. This is because it strongly depends on how and under what exact conditions and with wwhich tools you did the experiment. Think of this: If every methanol molecule reacts (burns) at once all at the same time, then the exact same amount of energy is spent, but it went really ...


1

I guess the Alka Seltzer is an effervescent kind of tablet. When it is immersed in water, gas bubbles form on the tablet surface and surface tension effects prevent the bubbles from separating them from the tablet surface. By this effect the global density of the system tablet plus bubbles is going down overtime, until the global density approaches the ...


1

In fact, the water would act as a neutron moderator, speeding up the reaction. However, reactor pressure vessels are quite sturdy, and it would be very unlikely for the salt water to enter the pressure vessel.


1

If you look at this table you will see that water, even without the phase transition, actually has the highest volumetric heat capacity of any of the substances listed (absent any phase transition materials). This means that an ice cube is indeed the best you can do for cooling down your drink. Even when you take account of the heat of fusion, water is ...


1

You can try ice cubes made of soda for having only soda. You can try having spherical cubes instead of small cubical ones, which take more time to melt. Or else try adding some salt to the water and freezing it. It reduces the freezing temperature of ice which makes the ice freeze faster and melt slower.(But 10 gm of salt in 10 litres make a change of 0.1 ...


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A somewhat longer answer, since I'm afraid my comment may have seemed a bit abrupt... Lets look at a fairly simple thermodynamic system, the Ag-Ge binary phase diagram. This consists of 3 phases only, fcc Ag, diamond cubic Ge, and the liquid. Taking the published thermodynamic model from J. Wang et al. in Thermochimica Acta 512 240-246 (2011), one can ...


1

Just before the ball reaches the ground, all of its molecules are coming down with almost an equal speed that is the speed of the ball.(Although, due to the non-zero temperature of the ball, the molecules are also vibrating about their mean position wrt COM frame of the ball).And thus the ball possesses a systematic macroscopic kinetic energy. Now when ...



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