Unit 1 Reflection

In this introductory unit to Physics, I learned about basic concepts. I learned about forces and different concepts from both Newton and Galileo. This unit covered inertia, velocity and acceleration and all of the properties surrounding them. Initially I thought of Physics as a scary topic due to my past experience however after this first unit I have become less terrified of the idea. In this introductory unit I learned that physics is what surrounds us. It occurs in our everyday life eg/ walking, jumping, driving.. I was taught basic physics in Bermuda and was introduced to more difficult concepts such as simple harmonic motion and projectile motion. In this unit I re-learned concepts regarding acceleration and velocity and how they differ. Velocity is directional speed whereas acceleration is in increase or decrease in speed over a unit of time. To introduce newton’s first law of motion; every object in motion will stay in motion at uniform speed unless acted on by an outside force. So why does a car gradually slow down on the road? It is because friction slows the car down. When we remove this force with a hovercraft, once in motion, the hovercraft will travel at uniform speed unless acted on by an outside force. Since friction is present in our world it is impossible for an object to move at uniform speed unless it is counteracting the force of friction. Another interesting theory we went over is the significance of head rests and how they help when we suddenly go forward. Interestingly enough, since the car suddenly goes in motion our head want to stay at rest. Since our head wants to stay at rest the headrests prevents us from damaging our neck. Similar to a ball thrown up in the air, it will keep moving up simply because nothing is preventing it from going up. Our head will fall back unless something prevents our head from falling back. A race car driver wins a race through acceleration. Acceleration is the change in speed over a unit of time. The formula to express this is; V=at (Velocity= acceleration x time) The race car driver also wins the race since he/she is maintaining higher velocity than the other race car drivers. The velocity will change once the direction has changed. For instance if the race car driver turns around a curve, the car is momentarily accelerating and changing velocity since the direction is being changed. Constant velocity is the constant speed of an object. Constance acceleration is the constant increase in speed over a certain amount of time. The equation to calculate the distance of an object traveling at a constant acceleration is as follows; d=.5(a)(t)2 (distance=.5(acceleration)(time)2) I have learned that an easy way to solve a physics problem is to understand the variables in the question. The trip problem demonstrates a classic example of how our brain works. When we are provided with numbers we tend to overlook important aspects in the problem. It is vital to underline all variables present in the problem. Here is a problem that people tend to mess up on; What is your acceleration if you drive 60mph for 1 hour? The answer is that you are not accelerating since you are traveling at a constant velocity. Do you see how it is easy to become overwhelemed when presented with numbers. To solve this problem, write the acceleration formula and the corresponding unit. You will quickly realize that you cannot solve it since you do not have a value for acceleration. I found this difficult to comprehend initially since I was presented with numbers. I overcame this problem by using the technique mentioned earlier. Writing out all the variables and the formula for the unknown is an easy method to overcome this problem. This allows you to visually see the unknown variables and what needs to be solved. My goal for the next unit is to overcome this problem of mine and to not let any question confuse me. I plan to use this method on any problems I find confusing. We studied constant acceleration, constant velocity, newton’s first law and many other concepts. All concepts have real world application. An example of constant acceleration is a plane taking off at full throttle. The plans speed is accelerating constantly per unit of time. An example of constant velocity would be a ball rolling on a flat plain. Newton’s First law of motion can be demonstrated through a hovercraft of the movement of asteroids. All occur every day in and outside of our world. For more information regarding constant velocity click on the you-tube video!!