Double exercise.
I use Google translator for help myself in this exercise.
Feel free to correct me!
I have thougth to do a tutorial about the use of an hammer.
First advice is signalize that it is a heavy tool, therefore it has to be used carefully.
Image 1.
Look to the positon of hands. In all the photografies; it is very important.
Image 2.
Lift the head of hammer vertically. In that movement you give to the hamer the potential energy.
Image 3.
Idem.
Image 4.
Look that slide down of right hand.
Image 5.
Look that the head of hammer, is doing a parabolic path. This earn with little effort an important velocity.
Image 6.
And 8 kg. of iron impacts against ceramic pieces.
Note.
Really, previous images are static, for this reason positions are a bit unrealistic.