Hammer

Hammer

Hammer is a force amplifier.

Parts of hammer:
1. handle axis
2. Eye
3. Peen
4. Neck
5. Head
6. Strike surface

Physics of Hammer:

ME=KE=ME.

Let us assume that a hammer strikes an object with force F, with distance between the hammer and an object before striking be D. Then the recoile distance be d and force of recoil be f- reaction force.

Then,
Energy= Force * Distance travelled* gravity

here conservation of energy is in action. So,

F*D*g=f*d*g

Therefore
f=D/d*F

Here the force is being multiplied by a factor of D/d.

The recoil percentage is the force multiplication factor.
For eg:
A titanium head gives a recoil value of 3%.
A steel head gives a recoil value of 30%.

Effect of Head mass
If we consider 2 hammers, lets say titanium and steel, of different masses, m1 and m2.

and m1<m2

KE= 1/2 m v^2

now KE is directly proportional to m and square of velocity.

KE1=1/2 m1 v1^2   titanium
KE2=1/2 m2 v2^2   steel
For m1<m2
KE1=KE2,
v1>v2 for this to happen.

again v is directly proportional to effort arm.

there for for more v=== arm should be longer.

Therefore to produce a same KE by two different massed hammer. The effort arm of smaller massed hammer should be longer and vice versa.


Classification of hammer according to Hardness:
a) Hard Hammer-steel
b) Soft Hammer- wood,nylon,rubber/plastic/copper/lead/brass

Classification according to structure of peen:
a) Straight peen
Peen parallel to the handle axis.


b) Cross peen
Peen perpendicular to handle axis.


c) Ball peen
The peen is of ball shape.

d) Modified peen
Modification for removal of nail etc.