Bowling Ball At A Constant Speed example essay topic
A lot of the web sites were brief descriptions. A guy named Paul Durbin wrote many articles on physics. One of his articles he discussed was about bowling. He mentioned one thing we already went over this semester in physics class. But it seems to me that he neglected to mention other forces the play a big role in bowling and the physics behind it. Durbin said "In order to accelerate, you need a net force.
As soon as I let go of the bowling ball, it's accelerating. As soon as your fingers are out of the holes, the ball is at its highest point of acceleration (p. 2)". According to the author, gravity is the net force acting upon an object, which means it is accelerating. The swinging of my arm (back the forward) being the net force. When my fingers leave the hole, it's accelerating. Now, how fast it goes is determined on how fast you swing your arm and let go.
Now that's all Durbin basically said on bowling. But I realized that Newton's Laws, momentum, kinetic and potential energy all have their role in bowling too. Durbin was correct when he explained acceleration. Let me tell you a little something on acceleration. Acceleration is the rate at which the velocity is changing. Because acceleration is a rate, it is measured of how fast the velocity is changing with respect to time of course.
The key idea that defines acceleration is change. Whenever we change our state of motion, we are accelerating. A bowling ball that can accelerate fast has the ability to change its velocity pretty fast. A bowling ball that can go from zero to 5 mph in. 5 seconds has a greater acceleration than another ball let go by another player that can go from zero to 7 mph in 1 second. (We learned about this in class).
So having a high acceleration is being quick to change and not always fast. Acceleration applies to changes in direction as well as changes in speed. When you let go of the bowling ball at a constant speed of 5 mph you may not be able to feel the effects of acceleration but you know (because of physics) its accelerating. You may let go of the bowling ball at a constant speed, but its velocity is not constant because of the change in direction every instant. The ball's state of motion is changing. It's accelerating!
Now you can see why it is important to know the difference between speed and velocity, and why acceleration is defined as the rate of change of velocity, rather than speed. Acceleration is like velocity, its directional. If you were to change your arms speed or direction, or even both, you change velocity and you accelerate. Just remember acceleration = change of velocity / time interval. The one thing that's cool about pool is that wooden alley that's always shiny. The alley is made out of fine wood and is usually shined up.
The alley seems to be the friction that slows a ball down. Even when a single force is applied to an object, it is usually not the only force affecting the motion. This is because of friction. Friction is a force that always acts in a direction to oppose motion.
When you let go of the ball one way, the air resistance is coming the opposite direction. Let go of the bowling ball and you can see it in motion. If an object moves, the by virtue of that motion it is capable of doing work. It has energy in motion, or kinetic energy. The kinetic energy of an object depends on the mass of the object as well as its speed. KE = 1/2 mv^2.
When you let go of that bowling ball, you do work on it to give it speed to get that nice rotation. The moving ball can the hit something (pins or unfortunately... the gutter) and push it, doing work on what it hits. The kinetic energy of the ball is equal to the work required to bring it to that speed from rest or the work the object can do in being brought to rest. Let's go back to KE = 1/2 mv^2. Note that the speed is squared, so that if the speed of an object is doubled, its kinetic energy is quadrupled (2^2 = 4).
(This information I got from reading ahead in the physics book). This means it takes four times the work to double the speed. Also, an object moving twice as fast takes four times as much work to stop. So now we have talked kinetic energy.
Conservation Of Energy! More important than being able to state what energy is, is understood on how it behaves or in this case, how it transforms. As you make contact with the bowling ball with the pins, you do work in hitting the pins. Your arm has potential energy.
When you let go of the bowling ball, the ball has kinetic energy equal to this potential energy. It delivers this energy to its target. Energy changes from one form to another. It transforms without net loss or net gain. Let me explain this better... Law Of Conservation Of Energy: Energy cannot be created nor destroyed, it may be transformed from one form into another, but the total amount of energy never changes.
Let's assume that the cue ball has 10 J of PE. As it's hit, PE is at its highest (10 J). When the ball is going down the alley, the sum of the ball's PE and KE remains constant at successive positions 1/4, 1/2, 3/4, and all the way down. (This I also read ahead and found in the book). As soon as the ball has reached its highest point, PE and KE are equal (5 J), and on the way down KE increases as PE decreases. When the ball lands, KE is 10 J and PE is 0.
Law of Conservation of Momentum: In the absence of an external force, the momentum of a system remains unchanged. When you hit the cue ball, you have a natural follow through. When you apply that torque (extending the elbow), your momentum changes. You can see that if no net force or impulse acts on a system, then the momentum of that system cannot change. Some of things mentioned, are things we know that happen, but we don't know why, and usually never wonder why, but for all things, there are explanations, which some of the secrets of mother nature were revealed here.
Just remember that there are physics behind whatever you do or see including bowling with your girlfriend (s)..