Why is Centrifugal force “not real”? I remember my physics teacher in high school pushing that idea and understanding why back then, but I do not remember now. I also forgot so much about physics in general that a simple would be much appreciated!
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Isn’t what we refer to as centrifugal force actually centripetal acceleration?
Because it is not but a subjective feeling of effect.
Imagine you are in car which started to make tight left turn. You feel you are pushed to right. However you are not pushed to right, your body attempts to move straight. Only car moved left and that create feeling you are pushed away from turn.
Same principle applies to all objects – they trying to move straight while something pulling them to side direction.
Isn’t what we refer to as centrifugal force actually centripetal acceleration?
You need to be really careful about the context of “not real” here.
There’s a tacit assumption in most physics problems that your reference frame (the coordinates you’re measuring everything against) is “inertial”, which means it’s not accelerating. There’s a bunch of reasons we do this, but one of them is that dynamics gets a lot more complicated if the reference frame itself is accelerating. This gets dealt with during university physics but usually not before. One of the complications is you get what totally seem like real forces but they don’t have any apparent source within the reference frame.
Centrifugal force is one of these…it absolutely acts like a real force, and if you’re *in* the accelerating reference frame you’d better treat it as real because it’s real in the sense that it pushes on stuff and you need to take it into account. But if you step out of the accelerating frame into an inertial one, you’ll see there’s nothing pushing that direction…it’s a side effect of the fact that your reference frame is accelerating.
Coriolis force is somewhat similar…it looks like stuff gets “pushed” sideways when you move closer or farther from the center of rotation but there’s nothing actually pushing it, it’s a side effect of being in a rotating reference frame. But it’s very real…among other things, it’s why weather systems rotate the way they do.
Because it is not but a subjective feeling of effect.
Imagine you are in car which started to make tight left turn. You feel you are pushed to right. However you are not pushed to right, your body attempts to move straight. Only car moved left and that create feeling you are pushed away from turn.
Same principle applies to all objects – they trying to move straight while something pulling them to side direction.
Because it is not but a subjective feeling of effect.
Imagine you are in car which started to make tight left turn. You feel you are pushed to right. However you are not pushed to right, your body attempts to move straight. Only car moved left and that create feeling you are pushed away from turn.
Same principle applies to all objects – they trying to move straight while something pulling them to side direction.
You need to be really careful about the context of “not real” here.
There’s a tacit assumption in most physics problems that your reference frame (the coordinates you’re measuring everything against) is “inertial”, which means it’s not accelerating. There’s a bunch of reasons we do this, but one of them is that dynamics gets a lot more complicated if the reference frame itself is accelerating. This gets dealt with during university physics but usually not before. One of the complications is you get what totally seem like real forces but they don’t have any apparent source within the reference frame.
Centrifugal force is one of these…it absolutely acts like a real force, and if you’re *in* the accelerating reference frame you’d better treat it as real because it’s real in the sense that it pushes on stuff and you need to take it into account. But if you step out of the accelerating frame into an inertial one, you’ll see there’s nothing pushing that direction…it’s a side effect of the fact that your reference frame is accelerating.
Coriolis force is somewhat similar…it looks like stuff gets “pushed” sideways when you move closer or farther from the center of rotation but there’s nothing actually pushing it, it’s a side effect of being in a rotating reference frame. But it’s very real…among other things, it’s why weather systems rotate the way they do.
You need to be really careful about the context of “not real” here.
There’s a tacit assumption in most physics problems that your reference frame (the coordinates you’re measuring everything against) is “inertial”, which means it’s not accelerating. There’s a bunch of reasons we do this, but one of them is that dynamics gets a lot more complicated if the reference frame itself is accelerating. This gets dealt with during university physics but usually not before. One of the complications is you get what totally seem like real forces but they don’t have any apparent source within the reference frame.
Centrifugal force is one of these…it absolutely acts like a real force, and if you’re *in* the accelerating reference frame you’d better treat it as real because it’s real in the sense that it pushes on stuff and you need to take it into account. But if you step out of the accelerating frame into an inertial one, you’ll see there’s nothing pushing that direction…it’s a side effect of the fact that your reference frame is accelerating.
Coriolis force is somewhat similar…it looks like stuff gets “pushed” sideways when you move closer or farther from the center of rotation but there’s nothing actually pushing it, it’s a side effect of being in a rotating reference frame. But it’s very real…among other things, it’s why weather systems rotate the way they do.
The other commenters have done a great job explaining, but just FYI, in my first year of my degree, my lecturer said “okay now we’re out of school, is everyone comfortable with centrifugal force existing again?”
What he meant by that was that centrifugal force is a mathematical construct; but SO IS LITERALLY EVERYTHING ELSE so it’s just as “real” as any other force…
The other commenters have done a great job explaining, but just FYI, in my first year of my degree, my lecturer said “okay now we’re out of school, is everyone comfortable with centrifugal force existing again?”
What he meant by that was that centrifugal force is a mathematical construct; but SO IS LITERALLY EVERYTHING ELSE so it’s just as “real” as any other force…
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