Recent content by Andrew Mason

The internal energy is a thermodynamic property of a system and it is a function of its thermodynamic state. If the work done on the system is done by some means other than a thermodynamic process, (e.g. lifting a volume of gas in a fixed volume container in Earth's gravitational field) there...

Those definitions are a bit confusing as they use velocity in the definition of relative velocity. I would suggest that a better and less confusing definition of velocity of A relative to B at time ##t## is the time derivative at time ##t## of the displacement of A relative to B in the...

??? The velocity of the carriage relative to the fly is the time rate of change of the displacement vector of the carriage to the fly. In this diagram, ##\vec{v_{c-f}}=\dot{\vec{FC}}##: But ##\vec{FC}=\vec{R}-\vec{OF}## so...

I am not clear on the facts. Is the fly prescribing circular motion about O in the clockwise direction? In any event, velocity of the fly relative to the carriage frame would just be: ##\vec{u}-\vec{v}## where the velocity vectors ##\vec{v}\text{ and } \vec{u}## are constant magnitude but one...

Thanks for posting this. This article suggests the oldest formations that show no signs of having been affected by a seismic shift are about 12,000 years old. "Based on the data, we think that the fault may be at a relatively late stage of a seismic cycle, having accrued a slip deficit, or...

Ok. Suppose the top vertical scale was directly connected to the rigid (but massless) pulleys and frame like this:

The anomaly is that 25 appears to cost less than 20. AM

It is not clear what you are trying to equate. I will answer this on the assumption that you are trying to equate internal energy for the same mass of water at different external pressures. The air pressure at 10 m above sea level would be about 101.2 kPa and at 1800 m it would be about 83.6...

This might help. Gravitation, Misner, Thorne & Wheeler, 2017, page 4: AM

In a reversible Carnot cycle beginning with the forward heat engine direction, if one stores the output work and then applies that work to the reverse cycle, one would return to the initial states of system+surroundings - in which case |Qh| is the same in both as is |Qc|, with the heat flow Qh<0...

For any heat engine or heat pump ##W=|Q_h|-|Q_c|##. Since W is not 0 in either a heat engine or heat pump, ##|Q_h| \ne |Q_c|##

Rutherford would have known how many atoms were in a mole of gold using Avogadro's number. That number had been accurately determined from Milliken's oil drop experiment to determine the charge of an electron compared to a Faraday, which is the charge of a mole of electrons. So he would have...

The mass of a basic unit would be one kilogram divided by the number of such units in a kilogram. The problem Newton had was that he did not know that that basic unit was. At the time, it was by no means obvious that all matter consisted of the same basic units. Gold was dense and had other...

It’s not particularly insightful to define mass as inertia. Newton understood that there was a relationship between gravity and inertia. If he had defined mass as inertia he would need a different definition for mass as the source of gravity. So he defined mass to be something that was common...