This past week we finished off the week with an egg drop lab. This brought together the whole unit on momentums. The purpose of the egg drop lab was to build a capsule that would be able to keep an egg inside it alive from a 30+ foot fall. The capsule could be no bigger than 35cm x 35cm x 35cm and all supplies must be from your own home. I used a simple setup. A bottom heavy leveled out portion, a collapse zone, and a platform with half a 20 oz. water bottle which held the egg inside. The bottom of the capsule was meant to absorb the majority of the shock from the impact. To keep it level I put in a can half filled with water sideways so the capsule didn't fall the wrong way. The collapse zone was just 4 drinking straws placed in the four corners of the bottom box with about 3 cm exposed. On top that was the platform that held the egg capsule. The egg capsule was half a 20 oz. bottle, a cardboard bottom, with cotton and some old shirt for cushion. The drop was a success surprisingly because it landed at an angle. I guess most of the shock was absorbed through the bottom anyway.

Continuing on the unit of momentum, we did a lab that showed us more examples of different types of collisions. Some elastic equations, examples of conservation of momentum, and impulse. Ultimately I learned to think logically about momentum. I learned that if you lengthen the contact time of any collision the more impact is absorbed and sent through the object, and the opposite for a short contact time. When golfing the impact of the club hitting the ball is absorbed through the shaft of the club, the shorter contact times tend to give more shock, but the longer you hold through the ball, the more it is absorbed and you feel less shock. This is an example that shows a collision of a still object and a fast moving object. Of course, the faster the club hits the ball the farther it travels, to an extent because in the physics of golf, it depends on the angle, and power of the impact zone. This is just something I see all the time when I golf, didn't realize it was always there.

Our class is on the second week of momentums. Again with the basics, momentum is mass x velocity. It is a vector unit. Large objects moving slow can have the same momentum as a small object moving fast. So it is possible that a drinking straw if picked up during a storm or something and gains enough speed it can puncture through wood. What do you think would happen in a collision between two cars if (1) the cars are the same mass, (2) one cart is two times the size of the other and (3) they have different speed variables? All of this can be found using formulas and basic physics. Take in to consideration the law of conservation of momentum also, that is Pin=Pout (momentum in=momentum out). The picture shows a head on crash between a big truck moving at around 10 km/h and a little car going 30 km/h. This is an example of a real life scenario. A lot of times if it is a head on crash it is fatal depending on the impulse of the crash, which is caused by the momentums of both vehicles. This is because momentum is transferred between objects, Pin=Pout. Its logic thinking from there.If one car is going North and one East and they collide the end result will be a lot different than a head on crash. You can find what direction the crash will end up at and what speed it was be using physics formulas to solve momentum problems.

Momentum. I can describe momentum as a force or something moving in a direction that builds force over time. In sports, especially football, the ball carrier develops momentum through his run. If he is fast enough to build momentum quickly, he/she may be harder to tackle. That is why if someone 6'2", 230 lbs, gets into open field and starts running down hill its going to be very hard for someone to tackle that person because its going to take a lot to change the direction of the ball carriers momentum. The key to taking someone like that down is hitting them in the hole before they develop anymore momentum. That is one example I can think of, off the top of my head. Other things like cars, trains, any type of transportation of moving thing has momentum. Scientifically, momentum is a vector quantity. It is the product of mass and velocity. But overall that is my explanation of momentum. A force that develops over time in one direction.

As we learn more about the different Newton laws, we had assignments to draw out free body diagrams, which show something happening and all the forces acting on it. One example I remember is something being suspended in the air, its like the opposite of something resting on a table. The picture above shows a light bulb being held in mid air by a wire. The reason that the light bulb isn't free floating is because gravity is acting on it. It causes the light bulb to hang freely. The reason it doesn't fall is obviously the wire, but the wire has tension, the normal force. Just as if a box resting on a table. The normal force is the table pushing back on the box, causing it to stay at equilibrium. The tension in this case is the same thing as the tables force normal. When going over examples on a work sheet I didn't realize how common these things are, it shows how physics works around us everyday.