bdavis

i admire your spunk my friend. But even in your tired state, you still came up with a valid physics concept and related it to an everyday occurrence. i can't tell you how many times i drop my eraser and know i know that if i have a similar eraser, that is how much energy is being transferred from potential to kinetic energy.

There are many sharp turns we encounter when we drive at high speeds on the highways. And even just driving straight down a highway, cars can lose control and accidents can happen. Friction is a concept and a force that plays a huge role in keeping cars on the road. The coefficient of kinetic friction, Meu, is what measures the ratio of the force of friction and the normal force of the object on that surface. It can help us find the maximum speed at which the car can stay stable on the road before it will lose contact. The higher the coeficient of kinetic friction, the higher the maximum speed will be before the car loses contact. Ice and water lower the coefficient of kinetic friction because it makes the surface much more slick and slippery. So on a rainy or snowy day, it is best to go slower because getting in an accident is much more likely in those conditions. Friction is definitely a concept that we should consider in our everyday lives to be safe drivers in all conditions on the road.

One activity i love to do is ski. I love the exhilarating feeling of going really fast down a steep incline. But in order to attain a fast speed, one must have good form to minimize AIR RESISTANCE. If someone were to go down a steep trail with their torso revealed with their arms extented out, they will reveal a ton of surface area and thus, the air will have more to make contact with. In turn, that person will not go as fast as they possibly could. But if someone has good form that can minimize air resistance, such as tucking their arms and shoulders in and crouching down so less of their body is exposed to headwind, then they will be able to go a lot faster. The air resistance will be reduced and their speed will increase. My knowledge of physics can help me improve my speed and time down the mountain. i knew there were reasonable applications for physics!

Many people might not think it but the meat-heads who body build conduct physics related actions everyday when they go to the gym. The weights they lift are objects that apply a force to the muscles that are targeted in different exercises. Newton's second law, net force= mass x acceleration (F=ma) shows that force is equal to the mass times the acceleration. So the weights that people lift when they work out have a mass that is accelerated by gravity to produce the force overcome by muscle movement. Building muscle mass can be attributed to Newtonian laws of Physics!

i have always been curious how it would be to drop an object from the top of the empire state building. It is obviously a long way down but exactly how fast would an object be traveling once it hit the ground? If i were to drop a golf ball for example, how fast would that travel? Well we can do this using my knowledge of one dimensional motion, a key physics concept. Acceleration due to gravity is -9.81 m/s for any object no matter the mass. Using our kinematic equations we can find out the final velocity any object will attain once it reaches the bottom of the Empire State building. The height of the empire state building is 443 meters tall. That will be our delta Y. Our acceleration is gravity which is -9.81 m/s. Our initial velocity is 0 m/s because we are dropping it from rest. We don't need the time in order to find the final velocity so we will use the equation Vf^2=Vo^2 + 2ay. That will be Vf^2=0 + 2(-9.8)(-443). Vf=93.18 m/s. That would be really fast and could seriously hurt someone. That is really cool!

So the world series for baseball happened not too long ago and something amazing happened. Hunter pence, an outfielder for the San Francisco Giants, broke his bat when swinging at a pitch but his bat hit the ball three times after he made initial contact. http://www.youtube.com/watch?v=mOkbQVsIk_0 The ball made contact with the bat initially a few inches above the handle where he was holding it. In the video, you could see that the bat bent out as it was breaking and began to bend towards where the ball came off the bat. The bat and the ball collided in midair after initial contact and touched three times total. The physics involved with that is that the ball was traveling at such a high velocity and the bat was moving at a high velocity in the opposite direction, the bat couldn't withstand such a great force and it broke on contact. But the ball caused the bat to continue in its path towards the left where the ball was heading because it bent the bat on contact as it broke. Both objects were moving with the same speed coming off the bat and that is why they made contact a few more times. That doesn't happen often. The ball has to hit the right spot on the bat and the angle of trajectory of both the broken bat and the redirected ball have to be really close if not the same. If the bat was as light as the ball, they would have traveled together longer but the bat decelerated faster than the ball did due to higher air resistance caused by more surface to be exposed. Baseball has more physics involved than i realized!

Believe it or not, rubber bands display the law of conservation of momentum very clearly. When a rubber band is pulled back by a person applying a force to it, it doesn't have any momentum because the velocity of the rubber band is zero. So when the rubber band is released, it gains velocity and therefore has momentum. So then how would this action demonstrate conservation of momentum? Well, the rubber band causes the person who released it to experience a recoil force. Since the rubber band is much less massive than a human, the momentum we gain by shooting the rubber band is almost negligible but it still occurs. Therefore when shooting a rubber band, conservation of momentum is demonstrated.

I am a man who loves baseball and when i figured out that physics plays a huge role in pitching, i got excited. Physics is exhibited very well in curveballs. A curveball is a pitch that was named for its movement; it curves on its path towards home plate as it reaches the batter. The pitcher grips the ball on the side just over one of the seems and when he throws it, he flicks his wrist hard creating the ball to spin sideways as it travels forward towards the plate. As it shows in the diagram, the rotation on the ball creates high pressure as the seems turn over which eventually makes it turn hard and dip towards the end of its flight. The harder it is thrown, the more dropping action it will experience because the greater the high pressure will be. Hitters better watch out because physics is not on their side when it comes to hitting a curveball.

that is a very good point mr. panther. so that means if i were to punch you, i wouldn't actually be touching you. that is a very interesting concept.

The varsity cross country team decided to get mowhawks to get pumped up for thier sectional race this past saturday. As a member of the cross country team i got one as well. Most of our runners had long enough hair to spike it and create very large and excentuated mowhawks. I didn't have enough hair to do that so i got the sides of my hair shaved off and my mowhawk looks like a drag strip right down the middle of my head. This type of mowhawk has some very unique properties. As a runner, i want to maximize my time. My type of mowhawk provides less air resistance that would be provided by my hair. With less hair on the sides of my head, the air can move past my head easier and the strip in the middle of my head can help to split the air on either side of my head. Therefore, when running, a mowhawk may look kind of dumb if the person can't pull it off but it can help improve a runners times on a day where head wind is a problem.

We recently built catapults as a project assigned by our physics teacher. Our goal for this project was to maximize the distance of the projectile, which in this case was a softball. We either had the choice of building a catapult or a trebuche but we decided to build a catapult. Using our knowledge of two dimensional motion, we set out to build a catapult that would launch the projectile at the optimal angle with the most applied force. We placed a wooden beam on our catapult at the spot that would cause our arm to release the catapult at 45 degrees, the optimal launch angle. We used garage springs to provide the force to the arm to accelerate the arm until it reached its launch point. We pulled the spring back to the base of the catapult, stretching it a good amount to provide a good source of tension in the spring. That force pulled the arm of our catapult up, launching our projectile at the optimal angle (45 degrees) so it could attain its maximum height and distance. Our catapult launched the softball a maximum distance of 35 yards which was a very solid result to a project that tested our knowledge on a very important physics concept. We were proud of ourselves.

still waiting for my first noticeable "ding" moment. then understanding this stuff will come a lot easier after that

I am very interested in physics and in learning how different things work in the world around us. i class we learned the dot product and cross product and applied them briefly to kinematics in our first day of that unit. Although those are two very new concepts to me relating to vector math, i am interested in grasping the new concepts and applying them to my growing knowledge of physics. i wanted to take physics to gain more knowledge about what this area of science has to offer. i am very interested in sciences and i am planning on pursuing a career in medical research in the future. i hope to gain more knowledge about physics and being able to apply it to other areas of science to gain a better understanding of how things work. i am most excited to go more in depth in the material and better understand electrostatics and magnitism, my two most difficult units from last year. i am most anxious to get to apply the knowledge of kinematics to other areas of mechanics and learn more in-depth material. I anticipate learning a lot of new things and i am very excited.