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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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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66 Answers

Anonymous 0 Comments

You are sitting at a stop light. Dom Toretto pulls up next to you and starts revving. You are ready to throw down as well since you also live your life one quarter mile at a time.

The light turns green, you floor the gas. You are instantly pushed into your seat. But now think about the forces. The engine and wheels are providing a force forwards and the car is forcing you forward as you do 0 to 60. But you **feel** like you are being pushed backwards.

There is no real force pushing you into your seat; the real force is the car propelling you forward trying to catch Dom as all you see are his taillights. But it feels like someone is crushing you into your chair.

Anonymous 0 Comments

Imagine you’re sitting in your car and begin to accelerate forward. You feel yourself sinking backwards in your car seat.

If you closed your eyes you could easily believe that some mysterious “car force” is pulling you backwards into your seat. But if you open your eyes you’ll know there’s no force pulling you backwards. Instead your car seat is accelerating forwards and pushing you forward.

That’s what the centrifugal force is. If you’re sitting in a big rotating disc with walls (like the ones sometimes seen at amusement parks), you might think there’s some mysterious force pulling you outwards away from the ring, against the ring’s walls, but the reality is there is no such force, rather the ring walls are constantly accelerating you inwards to keep you spinning in a circle.

Anonymous 0 Comments

The idea of fake forces comes up in other places aswell, and I think a car is the easiest to intuitively understand.

So, you‘re sitting in a car and you hit the gas pedal. The only force in that scenario is the one that pushes the car forward. But for you it doesn‘t feel like that. It doesn‘t feel like you‘re being moved forward. Instead it feels like you‘re being pushed into the seat.

What you‘re feeling is not the force that moves you forward, but rather your own Inertia. Your body doesn‘t want to move forward but the car does, so your body is, in a sense, pushing against the car. This is the force that you think is there, when in reality it‘s not really there.

And the same goes for circular motion. If you drive straight forward and you want to turn left you need a force that pushes your car to the left. This time however it feels like you‘re being pushed to the right.

And again, that‘s not actual force you‘re feeling. It‘s your own inertia. Your body wants to keep on going straight, but the car forces you to turn left.

Anonymous 0 Comments

You are sitting at a stop light. Dom Toretto pulls up next to you and starts revving. You are ready to throw down as well since you also live your life one quarter mile at a time.

The light turns green, you floor the gas. You are instantly pushed into your seat. But now think about the forces. The engine and wheels are providing a force forwards and the car is forcing you forward as you do 0 to 60. But you **feel** like you are being pushed backwards.

There is no real force pushing you into your seat; the real force is the car propelling you forward trying to catch Dom as all you see are his taillights. But it feels like someone is crushing you into your chair.

Anonymous 0 Comments

Imagine you’re sitting in your car and begin to accelerate forward. You feel yourself sinking backwards in your car seat.

If you closed your eyes you could easily believe that some mysterious “car force” is pulling you backwards into your seat. But if you open your eyes you’ll know there’s no force pulling you backwards. Instead your car seat is accelerating forwards and pushing you forward.

That’s what the centrifugal force is. If you’re sitting in a big rotating disc with walls (like the ones sometimes seen at amusement parks), you might think there’s some mysterious force pulling you outwards away from the ring, against the ring’s walls, but the reality is there is no such force, rather the ring walls are constantly accelerating you inwards to keep you spinning in a circle.

Anonymous 0 Comments

Imagine you’re sitting in your car and begin to accelerate forward. You feel yourself sinking backwards in your car seat.

If you closed your eyes you could easily believe that some mysterious “car force” is pulling you backwards into your seat. But if you open your eyes you’ll know there’s no force pulling you backwards. Instead your car seat is accelerating forwards and pushing you forward.

That’s what the centrifugal force is. If you’re sitting in a big rotating disc with walls (like the ones sometimes seen at amusement parks), you might think there’s some mysterious force pulling you outwards away from the ring, against the ring’s walls, but the reality is there is no such force, rather the ring walls are constantly accelerating you inwards to keep you spinning in a circle.

Anonymous 0 Comments

The idea of fake forces comes up in other places aswell, and I think a car is the easiest to intuitively understand.

So, you‘re sitting in a car and you hit the gas pedal. The only force in that scenario is the one that pushes the car forward. But for you it doesn‘t feel like that. It doesn‘t feel like you‘re being moved forward. Instead it feels like you‘re being pushed into the seat.

What you‘re feeling is not the force that moves you forward, but rather your own Inertia. Your body doesn‘t want to move forward but the car does, so your body is, in a sense, pushing against the car. This is the force that you think is there, when in reality it‘s not really there.

And the same goes for circular motion. If you drive straight forward and you want to turn left you need a force that pushes your car to the left. This time however it feels like you‘re being pushed to the right.

And again, that‘s not actual force you‘re feeling. It‘s your own inertia. Your body wants to keep on going straight, but the car forces you to turn left.

Anonymous 0 Comments

The idea of fake forces comes up in other places aswell, and I think a car is the easiest to intuitively understand.

So, you‘re sitting in a car and you hit the gas pedal. The only force in that scenario is the one that pushes the car forward. But for you it doesn‘t feel like that. It doesn‘t feel like you‘re being moved forward. Instead it feels like you‘re being pushed into the seat.

What you‘re feeling is not the force that moves you forward, but rather your own Inertia. Your body doesn‘t want to move forward but the car does, so your body is, in a sense, pushing against the car. This is the force that you think is there, when in reality it‘s not really there.

And the same goes for circular motion. If you drive straight forward and you want to turn left you need a force that pushes your car to the left. This time however it feels like you‘re being pushed to the right.

And again, that‘s not actual force you‘re feeling. It‘s your own inertia. Your body wants to keep on going straight, but the car forces you to turn left.

Anonymous 0 Comments

Just to add to the other answers, yes, it only appears in a non-inertial reference frame.

You know what else is a fictitious force by that definition?

Gravity.

The sensation of gravity is the ground pushing you up to stop you following a “geodesic” (a path under free fall) to the centre of the Earth.

Astronauts on the ISS are in free fall, and thus in a pretty much inertial reference frame.

Whether a force is fictitious or not is kind of overblown IMO.

Anonymous 0 Comments

No, its fully real, problem people are digging into semantics too much.
is centrifugal force a force? No, it is not, it is a byproduct of mass moving at a velocity, changing direction fast enough for the mass to not be affected by things such as gravity.
Centrifugal force is real, its just not a force like the electromagnetic force.