# Using watts to help determine velocity?

• bluej774
In summary, an abstract object has mass, position, and all external forces acting upon it (gravity). It is also exerting force upon itself and has a direction. The object is using energy to produce the force, and its kinetic energy may have changed. If you know the object's position and force at a certain moment, you can calculate its velocity.
bluej774
Here's what I know about an abstract object:
*mass
*position
*all external forces acting upon it (gravity ;)
*that it is exerting force upon itself
*direction of said force
*number of joules per second being used in said force (watts)

Can I use these to determine the velocity of the object? If not, what other information do I need? It's important that the joules per second (watts) be a part of the equation.

as long as you can find a resultant force acting in one direction, you can calculate the velocity from the force and the power using P=F*v Power=Force*Velocity

Well, then, maybe this is a better question. Can you determine force from watts (joules per second) expended producing said force?

bluej774 said:
Here's what I know about an abstract object:
*mass
*position
*all external forces acting upon it (gravity ;)
*that it is exerting force upon itself
*direction of said force
*number of joules per second being used in said force (watts)

Can I use these to determine the velocity of the object? If not, what other information do I need? It's important that the joules per second (watts) be a part of the equation.

I think since velocity is the rate of change of position with respect to time, that without knowing some rate of change in position, as an initial condition, and the history of forces and energies affecting the object since, then you can't just tell from knowing all the forces acting on it at an arbitrary moment, because those forces result in accelerations, and those accelerations are only the rate of change of velocity at some point and don't necessarily speak to what it may be changing from or to.

I think you need to know it was at rest somewhere, or its velocity somewhere, and its history since to be able to determine what it's total kinetic energy (and hence velocity) is at the point of interest.

bluej774 said:
Well, then, maybe this is a better question. Can you determine force from watts (joules per second) expended producing said force?

J/s if you know the duration gives you joules and joules gives you energy added to the object and hence you know how much its kinetic energy may have changed.

But in reference to the prior post you only know how much it may have changed, and without knowing what it's kinetic energy is initially, then ...

I'm doing a simulation. That's why I need this info. I forgot to mention that the object begins at rest. However, the simulation is not in Earth's gravity. It is in a theoretical space without any major gravitational influence.

Well in that case yes.

You have position and it's at rest then all you need then is the forces and durations over its history to the moment of interest I'd say.

So, what is the equation to figure out force using joules per second?

## What is the relationship between watts and velocity?

Watts are a unit of power, which is defined as the rate at which energy is transferred. Velocity, on the other hand, is a measure of the speed of an object in a particular direction. The relationship between these two is that watts can be used to determine the velocity of an object by calculating the amount of power needed to maintain a certain speed.

## How can watts be used to determine velocity?

Watts can be used to determine velocity by using the formula P = F x v, where P represents power in watts, F represents force in newtons, and v represents velocity in meters per second. This formula shows that an increase in power (watts) will result in an increase in velocity, assuming that force remains constant.

## Can watts be used to determine velocity in all situations?

No, watts can only be used to determine velocity in situations where the force and power are known and remain constant. In real-world scenarios, other factors such as friction and air resistance can affect an object's velocity and make it difficult to accurately determine using watts alone.

## What are some practical applications of using watts to determine velocity?

One practical application is in cycling, where watts can be used to measure the power output of a cyclist and determine their speed. Watts are also commonly used in the field of engineering to calculate the velocity of moving objects such as cars or airplanes.

## Are there any limitations to using watts to determine velocity?

Yes, there are several limitations to using watts to determine velocity. As mentioned before, external factors such as friction and air resistance can affect an object's velocity and make it difficult to accurately determine using watts alone. Additionally, this method assumes that the force and power remain constant, which may not always be the case in real-world situations.

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