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5

Edited because I had misread the question If the goal is to keep the tea hot, you add the milk first. This will bring the temperature of the tea down by some amount $\Delta T$, and the cooler tea will now lose heat more slowly while you dissolve the sugar. I am assuming that since you cannot see the sugar in the milky tea, you will do what I do - you add ...


2

It needs energy to solve sugar in water because the enthalpy of solvent (water) and solute (sugar) is lower than the enthalpy of the final solution, solving is an endothermic reaction in this case[1]. Milk has already some sugar in it, the (in)famous lactose, so the enthalpy of tea+milk might be higher than the enthalpy of tea alone and the order "milk ...


4

If the processes are instantaneous, and you drink the tea at once after that, then it doesnt matter. A more interesting question would be, when to put the milk in the tea. Now it does matter if you wait first and then add the milk and drink - or if you add it at once and then wait and drink. Do you see, why? Also, in your formulation "you were asked to ...


1

The order doesn't matter. The reason is conservation of energy. The tea, milk, and sugar before the mixing have some initial energy, and the final tea will have some energy that depends only on its state (the tea doesn't have any kind of memory of how it got to that state). The energy difference between these two states is the additional energy associated ...


1

This demonstration using the Ruben's tube set-up might help. I always found this to be one of the most exciting visual demonstrations of sound waves.


0

I you have a small speaker then you could lay it down and put a small piece of paper on it.Although not visible to the naked eye, when the speaker is switched on , a small piece of paper placed on the speakers will serve a good way to visualize the movements of air particles. Also to give an idea of the intensity of sound waves the speakers can be brought ...


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Sound waves can be visualised, but I can not imagine how it could be made without special equipment. You can find many related photographs on the internet if you search for the "Schlieren photography".


1

Water freezes from the outside in, as the outside is exposed to the coldest temperature. Therefore any impurities as pushed inwards as the water crystallises. These impurities are then compacted in the centre of the ice, making it cloudy as seen in your photo.


0

Remember the heat needed to melt ice is higher than that to boil water. At the point when she inserted the ice into the container,the heat absorbed was enough to stop the water from boiling(reduced the latent heat of vaporization of the boiling water)


3

It's probably the temperature of glass itself. Speed of sound in solids depends on the elastic moduli (the choice of the modulus depends on the polarization of sound - in this case, it's mostly transverse motion, as you are observing glass oscillation). The change of the density of the hot air may also contribute. Possible contributions and why they can be ...


1

Glass contracts when heated. This means the individual molecules compact as they meet the heat catalyst. This is one reason for the resonance difference. But also: If you take two separate glasses and fill them at different levels of room temperature water you will find they have different resonant frequencies as well. So in your heated liquid experiment ...


2

Inside the bathroom after a shower, the humidity rises and thus, the feeling of more warmth as it pertains to higher temperatures(warm air holds more moisture than cold air). In other words, it may be a similar temperature just outside the bathroom but the rise in humidity inside will make it feel much warmer for a short time. The size of the room and other ...



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