Pendulum - maximum kinetic energy, maximum potential energy

[jimmy42]

Is it correct to think that a pendulum which is at equilibrium has full kinetic energy? Then at it's maximum amplitude it has full potential energy?

thanks.

 

[Delzac]

Yeah. Thats correct.

 

[jimmy42]

Is that energy transferred to the bob?

 

[Delzac]

When the bob starts off at its initial position, it has gravitational potential energy but no kinetic energy.

When it reaches the bottom ( i wouldn't say equilibrium) it will have max KE.
So yes, there is a CHANGE in the energy.

But the total energy that the bob initially had never changed.

 

[jimmy42]

So, if a bob has a mass of 10kg and it moves 10m in the x direction is the energy to get it there = mgh= so 10kgx9.81ms^-2x10m = 981J?

Thanks.

 

[Delzac]

You will need to calculate the absolute change in height.

Usually we take the vertical axis as y direction, and horizontal as x direction.

So when you say in the x direction do you mean horizontal? Cause if that's what you mean, then it is incorrect. You will have to take the change in height.