Recent content by songoku

Thank you very much for all the explanations Lnewqban, Gavran, haruspex, Steve4Physics

How can we get this information from the question?

You mean both bat and moth will detect frequency of 230.3 kHz?

I treat this question as two cases of Doppler effect. (1) When the sound wave travels from bat to moth Speed of sound = 222 x 1.5 = 333 m/s Frequency received by moth: $$f_1=\frac{333+v}{333}\times 222$$ (2) When the sound wave is reflected from moth back to bat Frequency received by bat...

Thank you very much for all the help and explanation kuruman, jbriggs444, Lnewqban, Herman Trivilino, Gavran, haruspex

Thank you very much for all the help and explanation jbriggs444, Chestermiller, Lnewqban, Gavran

When te straw is lifted, water level inside the straw will decrease causing the volume occupied by the air increases ans reducing the gas pressure. Is that correct? Thanks

I am not sure what you mean by "each side of the tap" but I will take position 1 to be at the 12 m above the tap and position 2 to be at the tap. Set: ##v_1=0## and ##h_2=0## $$P_1 + \frac{1}{2} \rho v_{1}^{2}+\rho g h_1=P_2 + \frac{1}{2} \rho v_{2}^{2}+\rho g h_2$$ $$P_1+\rho g...

In the first link there are several formulas for the pressure but I don't think using any of those formulas can result in P to be zero so can you elaborate more why the statement (i) is approximately correct? When deriving the equation, the pressure at max height is taken to be zero. But...

I would say it is possible. So if this situation happens, then the water won't flow even though the tap is open? Thanks

Approximately correct because the absolute pressure will be zero only at 0 K? Thanks

Assuming ideal gas and constant temperature, then as the water level drops, the volume increases so the pressure decreases. Not sure why. I just know they did No reasoning. I think I am correct. You mean it is possible for the water to stop flowing when the remaining height of water in the...

Thank you very much for the help haruspex and kuruman

But what this information has to do with "the water will still be flowing but eventually it will stop."? I mean even though the container is not sealed, the water will still flow out the tap when it is opened and will stop when the water runs out. I say statement (iii) is correct but the...

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water...