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if an object is considered freely falling when it is thrown upwards, or if it only becomes "freely falling" when it..actually is falling? the velocity goes down to 0 when it reaches maximum height. Shouldn't changing from an non-zero velocity to a zero velocity be considered a change in acceleration, since it is slowing down at that time? ...

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Although "fall" in everyday English means "to move to a lower position under the effect of gravity", in Newtonian physics "free fall" means any motion of a body where its weight is the only force acting upon it, even if that motion in a particular time period in question involves moving to a higher position. "Slowing down" or "speeding up" both describe a ...

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The phrase freely falling really means freely moving, that is nothing is pushing or pulling the object while it's moving. So the object is freely falling even when it's rising! Like all things Physics has its own special terminology and I'm afraid you just have to get used to it. Re the acceleration: the acceleration is the change of velocity with time. If ...

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Look at the velocity plot in that video. It's a straight line. That's a dead giveaway that acceleration is constant. There's nothing special about velocity going through zero. From the perspective of a frame of reference that's moving down at a constant velocity of 65 m/s toward the Earth, that ball is moving up throughout that 13 second interval (velocity ...

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a freely falling object does not have any support to hold it in place and does not have any propulsion. So, when an object is thrown, the moment that it leaves your hand, it is a freely falling object. This is why there is a change in velocity when you throw it upwards. It slows down to where it reaches a peak and then it speeds up as it comes down. A ...

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The principle of equivalence only applies to objects that are "sufficently" small over a timeframe that is also "sufficently" small. In order to feel tidal forces, an object has to have finite size, and if the tidal forces are measurably, then the object is not sufficiently small.

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There is a difference between "feeling the force" and "being stretched". If you imagine two balls connected by a spring, and falling towards a massive object, then the closer ball will experience a greater force and therefore "accelerate away" from the ball that is further away - the spring between them will stretch, and thus provide a force balance. A ...

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Since air creates a force that is approximately proportional to the square of the velocity, the acceleration for each sphere is $a_r = kv^2/m (where \text{ } k = \frac{1}{2} C_x\rho\ S)$ The net acceleration on each sphere is $a_n = g - a_r$. As the velocity increases, the $a_r$ increases until the net acceleration $a_n$ becomes zero $(a_r = g)$, and ...

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