In my assignment I found the height at which my hammer must

In my assignment I found the height at which my hammer must fall to deliver 500 J of energy. Which is 12.74 m. How do find out how long the hammer pendulum must be if my design calls for to test the hammer to cock 0 degrees (horizontal). This problem is based off Charpy impact tester.

weight of the hammer head is 4kg.

Solution

If any body falling from certain height it will have potential energy

Use potential energy equation = mgh

500=mgh

500/gh =m

m= 500/9.81*12.74 = 4kg