What is the direction of radial velocity using the right-hand rule?

In summary, when trying to find the direction of radial velocity, you should use the equation ##\mathbf{v} = \boldsymbol{\omega}\times \mathbf{r}## from rigid body dynamics. If you want to use the right-hand rule, point your fingers in the direction of the angular velocity and curl them towards the position vector. There is no need to use the right-hand rule when calculating radial velocity, it is always in the plane of motion and pointing towards or away from the center.
  • #1
rohit199622
6
0
when we need to find the direction of radial velocity should we move our right hand from the omega (angular frequency) vector to the radius vector ?or opposite ?
 
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  • #2
rohit199622 said:
when we need to find the direction of radial velocity should we move our right hand from the omega (angular frequency) vector to the radius vector ?or opposite ?

Radial velocity is always in the plane of motion and pointing directly towards or away from the center according to whether the distance from the center is increasing or decreasing. There's no right-hand rule involved; that only comes into play when you're calculating vector cross-products such as the angular momentum.
 
  • #3
I believe rohit is referring to the following equation from rigid body dynamics: ##\mathbf{v} = \boldsymbol{\omega}\times \mathbf{r}##. In this case, if you want to use the right-hand rule, you would point your fingers in the direction of the angular velocity and curl them towards the position vector.
 
  • #4
WannabeNewton said:
I believe rohit is referring to the following equation from rigid body dynamics: ##\mathbf{v} = \boldsymbol{\omega}\times \mathbf{r}##.

Ah - yes, that makes more sense. Thanks for the catch.
 
  • #5
wannabeNewton said:
i believe rohit is referring to the following equation from rigid body dynamics: ##\mathbf{v} = \boldsymbol{\omega}\times \mathbf{r}##. In this case, if you want to use the right-hand rule, you would point your fingers in the direction of the angular velocity and curl them towards the position vector.

thanks a lot !
 

FAQ: What is the direction of radial velocity using the right-hand rule?

What is the direction of radial velocity?

The direction of radial velocity refers to the direction in which an object is moving towards or away from an observer. It is measured along the line of sight between the observer and the object.

How is the direction of radial velocity measured?

The direction of radial velocity is measured using the Doppler effect, which causes a shift in the wavelength of light emitted by an object depending on its relative motion towards or away from the observer.

What is the significance of knowing the direction of radial velocity?

Knowing the direction of radial velocity is important in understanding the motion and behavior of celestial objects such as stars and galaxies. It can provide valuable information about the structure and dynamics of these objects.

Can the direction of radial velocity change over time?

Yes, the direction of radial velocity can change over time as the relative motion between the observer and the object changes. This can be due to factors such as the object's orbit, gravitational interactions, or its own motion through space.

How is the direction of radial velocity used in astronomy?

The direction of radial velocity is used in astronomy to study the movement and distribution of celestial objects. It is also used to identify and characterize planets, exoplanets, and other objects in our universe.

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