Recent content by thephy

Robphy is helping you to think and solve the problem by yourself. Details: 1) since 16C >4C, the third spot should be closer to +4C 2) the spots between the two charges could not be 0, since in this case, the field of the two charge is in the same direction. Thus, the spot should in the left...

Sound is heard on the far side of a barrier because it vibrates the lattice of the solid. And only when the f of sound is similar to that of the solid, the resonance vibration comes out and the sound is absorbed more because its energy is transmitted to the solid. That's my opinion.

Higher. Because the conservation of the energy. If you use the energy of the electricity, then the energy must convert into other forms.

It is due to the crystal model of solid. When the frequency of the sound is too low to cause resonance vibration with the atoms of the solid, sound waves are not highly absorbed by solid objects. And on the other hand, it is the fact that when the frequency of the sound is too high, sound waves...

A good theory is always based on the experiment. And luckily, the result of the experiments are always can be described exactly by math, such as by formulas or by geometry. It is funny that physics can be compatible with mathematics. And therefore we can predict some phenomenas by computations...

Thank you.

Thank you.

Please tell me what's their meaning?

Why is the average binding energy of iron is biggest? Are there some theories about it?