johnhemming wrote:UncleEbenezer wrote:johnhemming wrote:Objects that are falling where there is no atmosphere generally are accelerating.
Not in the familiar sense.
We are indeed in a world in which meanings are mutable.
Indeed
If we start out with a definition of the word falling
https://www.dictionary.com/browse/fallingFalling normally refers to the reduction of height relative to Earth, but could be some other planetary body. I personally would not refer to an object in orbit falling unless the orbit was decaying.
Hence my statement in respect of falling is true.
Not quite. You said "no atmosphere", which explicitly detaches you from Earth and puts you in space, where falling is indeed orbiting.
We might as well stick to classical relatively which is easier to understand. However, we should really be able to agree on the usage of words. Objects in orbit are accelerating because their direction of travel is continually changing. The speed is also changing to some extent.
Yep. The moon is constantly accelerating towards Earth, yet (in a geocentric frame of reference, and to a close approximation) returns every 28 days to exactly the same position and velocity.
That could be confusing to a reader whose experience associates the concept with a pedal called the "accelerator" in a car. It could start to look like Escher.
You can think about this in terms of pushing a boat on a frictionless ocean.
You could also just walk or drive around in a circle.
Re: the OP. In the case of a satellite in Earth orbit, to go faster around the Earth you fire the rockets in reverse to slow you down (and of course vice versa). That's because slowing down causes you to fall into a lower orbit, which means you're travelling faster!