Friction acts towards the nail in the block when you are pulling it out. In other words, it will try to keep the nail in the block and not let it be pulled out by the hammer.
The hammer or crowbar is applying force to extract the nail, and is opposed by the friction between the board and the outside surface of the nail.
push
new nail
Friction
Friction
The hammer or crowbar is applying force to extract the nail, and is opposed by the friction between the board and the outside surface of the nail.
push
new nail
Friction
nothing
no it is magnetism
Friction
concrete nail
A claw hammer
You can put lipstick on your nails but it'll come right off.
YES. When hamming a nail/spike, the nail encounters friction from target rubbing against the sides of the spike and also from taring through the target.
Its the law of the lever, the crowbar grips the nail with nearly immovable objects,it's claws, and at a great distxnce from the nail force is applied to remove the nail