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The air higher up is moving faster to the ground. Yes, this is mostly correct - at least in principle. However, the effect is tiny compared to the natural speeds of the wind, particularly in the higher atmosphere. This means that in practice everything you say is true but it can be ignored. More precisely, a point on the surface of the Earth on the ...

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"If you go straight up into the sky without accelerating in any direction except up, so you stay directly above the point you left off and just go straight up, you are travelling at the same angular velocity at your new altitude, but you are changing speed." Granting the first part, the second does follow. But that's not what happens. Ignoring atmospheric ...

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Although this has been answered many times already, anywhere on this site, the following holds: First law (existence of inertial reference frames) There exist in the universe some very particular reference frames where a point particle not subject to external forces moves in a straight line, i. e. $\dot{\textbf{p}}=0$. Second law (equation of motion in ...

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There is absolutely a gravitational radiation reaction and solving for it is one of the very active fields in classical relativity theory at present. Basically, particles with nontrivial masses distort the spacetime around them; this causes them to not move on geodesics of the "background" spacetime (the spacetime that one would have found had the secondary ...

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like the quantum mechanics if you could not measure something so that not exists/ how could you detect a mass if there is no force even if you get close to that to touch it you have a mass yourself so the force would appear and if not you are contradicting newtons law of gravity so the argument is not that simple mass and force are defined by each ...

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For the car to remain stationary, a person must exert a force equal to the wheel force accelerating the car. The wheel force exerted by a car's idling engine (in gear) is determined from engine torque, drivetrain gear ratios, and wheel radius: T_{wheel} = T_{engine}*GR_{trans}GR_{final} \qquad \Rightarrow \qquad \therefore F_{wheel} = \frac ...

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An average car, with manual transmission, can accelerate to a speed of around 3-4 m/s in a span of a couple of seconds while idling quite easily. Let us assume that the manual and automatic transmission provide roughly equivalent forces at this speed. Let us say it has a mass of around 1000 kg, which translates to a force of 2000 N on an average ( or a ...

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The answer will likely vary depending on the model of car you are looking at. People that regularly drive automatics know that the cars can start moving on their own without any throttle input. Sometimes, even on a slight uphill grade. Think about how much a car weighs and how hard you would have to push to get it moving. That's how much force the engine ...

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Well, let's go back to Einstein's paper from September 1905, which demonstrated the famous relation $E=mc^2$. It's quite short, and well worth a read. An English translation is available here. Note that at the time Einstein actually used $L$ where we would now use $E$. What Einstein does is he considers a stationary body (in some inertial reference frame) ...

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Well, you have Newton's formula $F=\gamma ma$ and Einstein's formula $E=\gamma mc^2$ so you could obtain a relation a little like $F=\frac{E}{c^2}a$ so that $\frac{Fc^2}{E}=a$ you can see from here that the greater the energy, the smaller the resultant acceleration. Even for two identical forces, if you divide it by a greater energy, you'll have a smaller ...

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