COLLISIONS

When two objects collide, their velocities change, as well as their momentum.
Momentum equals the mass of an object multiplied by the velocity it is traveling Our first scenario (Diagram 1-1) involves one moving object, heading directly towards another, with no forces being applied to either object A or object B.

EXAMPLE ONE
Object A is traveling at 50 meters per hour, with a mass of 5,000 grams. Object B isn't moving at all, with a mass of 5,000 grams. When Object A hits Object B, Object B will head in the same direction as Object A was previously going, and with the same rate, since Objects A & B have the same mass.

EXAMPLE TWO
Object A is traveling at 50 meters per hour, but this time with a mass of 4,000 grams. Object B isn't moving at all, with a mass of 5,000 grams. Object A is smaller in mass than Object B, so the two move together in the same direction as Object A was going. For sake of calculation, we'll say that it took Object A one hour to collide with Object B. Now you can find out the rate of the two objects by calculating Object A's momentum:
 (velocity) multiplied by (mass) equals (momentum) (50 meters per 1 hour) times (4,000 grams) equals (momentum) (50/1) times (4,000) equals (200,000) grams times meters per hour

EXAMPLE THREE
Another point to consider is when both objects are moving, and collide.
If two objects of equal mass ram into each other head-on, then they will bounceoff from each other at the exact opposite direction, yet at the same speed, since no other forces are acting upon it. This occurs due to Newton's third law: When object is applied with a force from an object, an equal but opposite force is exerted on the first object. In other, simpiler words; for every push or pull, there is an oppositely directed force.

EXAMPLE FOUR
If two objects of equal mass collide traveling diffent directions, their two velocities are averaged into one. For instance, If Object A's velocity is 4 meters per hour heading due North, and Object B's velocity is 5 meters per hour heading due East, then both objects will head Northeast, traveling:

(Object A's Velocity) + (Object B's Velocity)
1. {(4 meters per hour)squared + (5 meters per hour)squared}
2. {(16 meters per hour) + (25 meters per hour)}
equals
3. (41 meters per hour)
4. Square root the sum of Object A and B's velocity
5. Sq. rt. (41 meters per hour) = ( About 6.4 meters per hour)

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