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I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

If it helps, you can work out the velocity as a function of time in the case of a constant power:

$$F=\frac Pv=m\frac{\text dv}{\text dt}$$ $$\int_{v_0}^{v}v'\,\text dv'=\int_0^t\frac Pm\,\text dt'$$ $$\frac12\left(v^2-v_0^2\right)=\frac Pmt$$ $$v(t)=\sqrt{\frac{2P}{m}t+v_0^2}$$

And we can determine the force as well

$$F(t)=m\frac{\text dv}{\text dt}=\frac{P}{\sqrt{(2P/m)t+v_0^2}}$$

which is just $P/v$ as we come full circle.

So as you can see, over time the velocity increases and the force decreases in such a way that the power is constant. No other forces or $0$ net power is needed to explain this.

I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

If it helps, you can work out the velocity as a function of time in the case of a constant power:

$$F=\frac Pv=m\frac{\text dv}{\text dt}$$ $$\int_{v_0}^{v}v'\,\text dv'=\int_0^t\frac Pm\,\text dt'$$ $$\frac12\left(v^2-v_0^2\right)=\frac Pmt$$ $$v(t)=\sqrt{\frac{2P}{m}t+v_0^2}$$

And we can determine the force as well

$$F(t)=m\frac{\text dv}{\text dt}=\frac{P}{\sqrt{(2P/m)t+v_0^2}}$$

which is just $P/v$ as we come full circle.

So as you can see, over time the velocity increases and the force decreases in such a way that the power is constant. No other forces or $0$ net power is needed to explain this. Note that all of the above assumes a positive power.

I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

If it helps, you can work out the velocity as a function of time in the case of a constant:

$$F=\frac Pv=m\frac{\text dv}{\text dt}$$ $$\int_{v_0}^{v}v'\,\text dv'=\int_0^t\frac Pm\,\text dt'$$ $$\frac12\left(v^2-v_0^2\right)=\frac Pmt$$ $$v(t)=\sqrt{\frac{2P}{m}t+v_0^2}$$

And we can determine the force as well

$$F(t)=m\frac{\text dv}{\text dt}=\frac{P}{\sqrt{(2P/m)t+v_0^2}}$$

which is just $P/v$ as we come full circle.

So as you can see, over time the velocity increases and the force decreases in such a way that the power is constant. No other forces or $0$ net power is needed to explain this.

I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

If it helps, you can work out the velocity as a function of time in the case of a constant power:

$$F=\frac Pv=m\frac{\text dv}{\text dt}$$ $$\int_{v_0}^{v}v'\,\text dv'=\int_0^t\frac Pm\,\text dt'$$ $$\frac12\left(v^2-v_0^2\right)=\frac Pmt$$ $$v(t)=\sqrt{\frac{2P}{m}t+v_0^2}$$

And we can determine the force as well

$$F(t)=m\frac{\text dv}{\text dt}=\frac{P}{\sqrt{(2P/m)t+v_0^2}}$$

which is just $P/v$ as we come full circle.

So as you can see, over time the velocity increases and the force decreases in such a way that the power is constant. No other forces or $0$ net power is needed to explain this.

I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

I think the confusion is treating everything constant between power, force, and velocity, but this isn't possible.

If power is constant, then $P=Fv\to F=P/v$, meaning $F$ is a monotonically decreasing function of $v$. So when $v$ is "small", $F$ is "large". This causes an acceleration, which increases $v$ and decreases $F$. Note that this has to happen for constant power. There are no other forces present. You have said the power is constant for this process (whatever it is), and so the force has to be a function of $v$ as $F=P/v$.

If it helps, you can work out the velocity as a function of time in the case of a constant:

$$F=\frac Pv=m\frac{\text dv}{\text dt}$$ $$\int_{v_0}^{v}v'\,\text dv'=\int_0^t\frac Pm\,\text dt'$$ $$\frac12\left(v^2-v_0^2\right)=\frac Pmt$$ $$v(t)=\sqrt{\frac{2P}{m}t+v_0^2}$$

And we can determine the force as well

$$F(t)=m\frac{\text dv}{\text dt}=\frac{P}{\sqrt{(2P/m)t+v_0^2}}$$

which is just $P/v$ as we come full circle.

So as you can see, over time the velocity increases and the force decreases in such a way that the power is constant. No other forces or $0$ net power is needed to explain this.