Bahluku

Most that played pool with me before should know about my stunts. My ballz like to fly, some get to know that personally. My ballz hav hitten many hands, arms, fingers, belly and ****. But nvr meself. And today i hit my head whay.







I dun even know how it could happen la, the ball i wanna zham nt like stuck wad, how can it provide enuff support to let it bounce back to hit my head? But after thinkin with physics, maybe its possible.

This is most possibly an almost elastic collision.

An elastic collision is a collision in which the total kinetic energy of the colliding bodies after collision is equal to their total kinetic energy before collision. Elastic collisions occur only if there is no conversion of kinetic energy into other forms, as in the collision of atoms (Rutherford backscattering is one example).

In the case of macroscopic bodies this will not be the case as some of the energy will become heat.

The molecules — as distinct from atoms — of a gas or liquid rarely experience perfectly elastic collisions because kinetic energy is exchanged between the molecules’ translational motion and their internal degrees of freedom with each collision. At any one instant, half the collisions are, to a varying extent, inelastic collisions (the pair possesses less kinetic energy in their translational motions after the collision than before), and half could be described as “super-elastic” (possessing more kinetic energy after the collision than before). Averaged across the entire sample, molecular collisions can be regarded as essentially elastic as long as black-body photons are not permitted to carry away energy from the system.

Two-dimensional collisions

Newton's Rule (i.e. the conservation of momentum) applies to the components of velocity resolved along the common normal surfaces of the colliding bodies at the point of contact. In the case of the two spheres the velocity components involved are the components resolved along the line of centers during the contact. Consequently, the components of velocity perpendicular to the line of centers will be unchanged during the impact.

To solve an equation involving two colliding bodies in two-dimensions, the overall velocity of each body must be split into two perpendicular velocities: one tangent to the the common normal surfaces of the colliding bodies at the point of contact, the other along the line of collision. Since the collision only imparts force along the line of collision, the velocities that are tangent to the point of collision do not change. The velocities along the line of collision can then be used in the same equations as a one-dimensional collision. The final velocities can then be calculated from the two new component velocities and will depend on the point of collision. Studies of two-dimensional collisions are conducted for many bodies in the framework of a two-dimensional gas.

( all frm wiki, u can read it at http://en.wikipedia.org/wiki/Elastic_collision )

So i hav analyzed the problem and come out with a possible solution.

When i zham the ball with my bamboo bar. i think it is below the horizontal by a little.



So this will result in the ball to travel in this manner, assuming there is no air resistance


Taking upwards and leftwards as positive,

We assume that the ball hit the target ball while the Vy is positive



This would be the vectors





So according to my very detailed calculations, the zham'ed ball will fly towards the left.


So now for the 2nd scenario, da zham'ed ball hit the target ball when Vy is negative


Den the vectors will be liddat lor.



As u can see, in this case, the Vb is very large compared to Va, and in this case, i also included normal contact force.



Eh i skipped steps, cos first is the target ball normal contact with the table, den resolve plane, den get the normal contact force between the target ball and zham'ed ball den get the N below.



This is so exciting


So hence the ball will fly back and hit my head. In the case 1, i didn include normal contact cos the Vb is quite small, it will nt really affect the reading much. In case 2 den more significant.

There u go yang, i studied. Woo spent like 2 hours to draw them =/. Actually i wanted to say about my other stunts, like 3 balls fly together, coast to coast, aisle walk, leap of faith, etc. But now 1.10am liao. Time to sleep. =D.

Whay heroes only after common test. Whay.