Recent content by avast2

Thanks, I will search the book,

I searched some proof online but actually I want to find the proof of the kind of lever (such as Hammers pull the nails) Thanh you! I attach pictures ( - the proof that I had ; the kind of lever that I want to search the proof)

Does anyone has any documents to prove (law of lever)? Thank you!

I have a question about friction between pulley and rope? Does anyone know how to calculate friction between pulley and rope I enclosed an example picture Thank you!