- #1
greypilgrim
- 533
- 36
Hi,
Using conservation of energy $$m\cdot\ g\cdot\left(h_0-h\right)=\frac{1}{2}m\cdot\ v^2$$ it's easy to find the exact velocity of a pendulum $$v\left(h\right)=\sqrt{2g\cdot\left(h_0-h\right)}$$
at height ##h## above the minimum when it was let go from the inital height ##h_0##. Is it possible to derive this result from a dynamic point of view, i.e. looking at the forces at every height and integrate?
I know there is no elementary solution to the differential equation of the pendulum for angles beyond the small-angle approximation, but the simplicity of above expression for ##v\left(h\right)## might suggest that there's a way around this if one's only interested in the velocity.
Using conservation of energy $$m\cdot\ g\cdot\left(h_0-h\right)=\frac{1}{2}m\cdot\ v^2$$ it's easy to find the exact velocity of a pendulum $$v\left(h\right)=\sqrt{2g\cdot\left(h_0-h\right)}$$
at height ##h## above the minimum when it was let go from the inital height ##h_0##. Is it possible to derive this result from a dynamic point of view, i.e. looking at the forces at every height and integrate?
I know there is no elementary solution to the differential equation of the pendulum for angles beyond the small-angle approximation, but the simplicity of above expression for ##v\left(h\right)## might suggest that there's a way around this if one's only interested in the velocity.