# How do I use RotVelocity?

I need a part to have the RotVelocity be exactly right.

I would like to know what I should set the RotVelocity of a part if it was spinning at 360 degrees a second to. I would also like to know how the operation to figure this out in the future.

So I have tried multiple formulas to get it, such as degrees per second, or full rotations per second.

Thanks for reading.

What are you trying to do? It would help understand the problem you need solved.

If you want to make a part constantly turn a specific amount of degrees every second, youâ€™re better off using a BodyAngularVelocity.

BodyMovers have been â€śsoft-deprecatedâ€ť in that it tends to be a better option to use the newer constraint system, but thereâ€™s no formal deprecation due to the sheer extensive use of BodyMovers and the fact that the must still be supported.

To OP:
Personally Iâ€™d use a Torque in favor of BodyAngularVelocity, but either one works and itâ€™s on you to decide. Both work perfectly for the job. BodyAngularVelocity tends to be easier to use since thereâ€™s no attachment. In many cases you may find it easier to go with realhigbeadâ€™s answer.

I would prefer the object to be anchored

If an object is an anchored, then no physics will be applied onto the part. This includes all Forces applied by a BodyMover. To rotate the part, you need to directly manipulate the rotation view the partâ€™s CFrame property.

@EtiTheSpirit Keep in mind that Torque is different than Velocity (In this case, BodyAngularVelocity). Torque is analogous to a constant force that is applied to spin the part, which accelerates it. BodyAngularVelocity will maintain a constant rotational velocity of the part, which means 0 acceleration during steady state.

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You canâ€™t rotate an object if it is anchored.

Exactly. That is why I want to know what I should manually set the RotVelocity to

I donâ€™t think you read my post. RotVelocity will change the physical rotational velocity of the part. If the part is anchored, there are no physics calculations that are applied on the part. To make it move, you need to directly update the pose of the part: position and rotation.

Please only post if you are going to give a specific answer to OPâ€™s question, as â€śprobably use[ing] an equationâ€ť is not very helpful.

To answer OPâ€™s question directly, since no one will, RotVelocity uses Degrees per Second as itâ€™s unit. You can find this information on the Developer Wiki

This is what I mean: this part is anchored and has a rotvelocity of 1. I want to know the exact speed of how fast it rotates.

Testing in studio shows that the rotational velocity for that is in units Rad/Sec. It is strongly recommended you do not use RotVelocity that way, as it could result in unspecified and undocumented behavior.

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Thanks for your help! I appreciate it!