Reflection: Energy

Part A:

This is what I learned about the Conservation of Energy (COE). I learned that energy is a conserved quantity with the ability to produce change. Energy itself is non-changing, but it can simply be moved around and stored in different ways. In this unit, I learned about different types of energy storage. Some of these different kinds include elastic (Eel), gravitational potential (Eg), chemical potential (Echem), and kinetic (Ek). I also learned about internal energy, which involves friction. Internal energy is often found in the final stage of an energy bar diagram. When energy is transferred, the total amount of energy is conserved, which means the amount is the same and stays constant. Transferring energy from a type of energy storage to another is called "work". I also learned that there are three ways of energy transfer in or out of a system. The three ways are: working, heating, and electromagnetic radiation. During this unit I also learned how to construct a bar graph/energy flow diagram. In the diagrams, I use bar graphs to represent the initial and final energies. Some equations I used in this unit were: W=Fx (if F and d are in the same direction), P=W/t, KE=1/2(mv^2), PE=mgh, and PEe=1/2(kx^2).

I have also had some difficulties in this unit. I often get confused when I should use a net force equation in a problem. When there is a total amount of a certain energy, such as potential energy, I get confused about if I should add up the types of potential energy, such as PEg and PEe. Another thing I get confused about is when I need to find "h" sometimes. When a ramp is involved in a problem, I sometimes do not know when it is necessary to find "h" or "x". I believe that it is possible though to overcome my difficulties with these certain problems.

My problem-solving skills in this unit are a little under where they need to be I think. I feel like my weaknesses involve choosing which equation to use in problems. Some equations seem so similar to me that I sometimes forget they are different, such as the equation for PEe and KE. I feel though that this is just a memorization issue. If I take the time to study and learn these equations, I feel like my problem-solving skills in this unit will improve. My strengths include drawing diagrams for the given problem. Whether the problem involves a bridge, a ramp, or simply a flat surface, I feel like I can draw a diagram sufficiently. I definitely need to work some practice problems though.

Part B:

Energy and everyday life situations are connected in many ways. Every move we make involves energy in some way. For instance, I'll use a rollercoaster as an example. When the rollercoaster is at the top of a hill, it has little to no kinetic energy, but it has a lot of potential energy. Even if you are just mowing your lawn, energy is taking place. You are transferring energy into the lawnmower (at an angle). Energy is apparent everywhere.

Application: Force Glogster

This is my glogster about the forces involved with ice-skating. Click on the link below to find out about forces and what the centripetal force requirement is when ice-skating. My question is: What are the forces involved when someone is ice-skating (at constant speed) around the rink in circles and which one is the centripetal force requirement?
Kira's Force Glogster

Reflection: "Circular Motion and Gravitation"

I learned about circular motion, gravitation, and centripetal force. We learned before the difference between scalar and vector quantities, which comes in handy when it comes to centripetal force. Objects moving in a circular motion have a constant speed, but that doesn't mean the velocity will be constant since the object is changing direction. An object traveling at a constant speed in a circular motion is said to be in uniform circular motion. In order to obtain the velocity (m/s), one must figure out the distance and the period. To find the distance (around a circle's perimeter), you would use the equation: 2∏r. "T", the period, is the time that it takes to complete a full rotation. Also, an object is considered accelerating if it is changing direction. In circular motion, it's called centripetal acceleration. Acceleration is perpendicular to the velocity. Also, the inward force that keeps the object in a circular motion is known as the centripetal force. Moving on to universal gravitation, the Law of Universal Gravitation states, "Every object in the universe attracts every other object in the universe with a force that varies directly with the product of their masses and inversely with the square of the distance between the centers of the two masses." There is a lot to know about circular motion and gravitation!

What I have found difficult is drawing FBDs for objects in circular motion. I get confused as to where to place the arrow that describes where the acceleration is going. Also, I sometimes have finger problems when typing universal gravitation equations into my calculator. I believe that these difficulties can be solved over a short amount of time though.

I feel that my problem-solving skills are average. I definitely think that there is room for improvement though! On problems that aren't exactly like ones I have done before, I need to use similar skills used on previous problems rather than freaking out because I haven't seen anything like it. I feel that I am fairly good at figuring out the data I have and the data that I need to find out though. With some more practice, I can get my problem-solving skills to above average!

Newton's Second Law

Part A:

I learned about Newton's Second Law about acceleration and forces. Newton stated that "for a particular force, the acceleration of an object is proportional to the net force and inversely proportional to the mass of the object." In an equation, this would be a=∑F/m, which could also be seen as ∑F=ma. Newton's Second Law provides a concrete connection between force and acceleration. Also, the directions of acceleration and the force are the same. Also, in this unit, we worked with friction a lot. In order to get the net force used in Newton's Second Law, we sometimes need to know friction. There are two types of friction, static and kinetic. Static friction occurs when objects are at rest, and kinetic friction occurs when an object is in motion. With this information, it was possible to solve problems pertaining to forces and acceleration.

What I have found difficult is knowing what equation to use. I find it challenging to set up an equation sometimes because it confuses me on when to set the equation to equal zero or m×a. Once I figure out the correct equation, though, I can solve the problem without much confusion.

I feel that my problem-solving skills are accurate enough to succeed in honors physics. In other words, my problem-solving skills are average. As mentioned in reflection 1, I sometimes get impatient and frustrated when I can't figure out how to solve a problem. I do, however, feel confident in drawing FBDs and solving for the unknown once I have figured out the equation to use. My weaknesses include occasionally forgetting to multiply the mass by 9.8 in order to get the weight of an object, or visa-versa. I do feel, though, that I can solve the majority of problems without a hitch.

Newton's First Law

Part A:

I learned about Newton's First Law about translational equilibrium. Newton stated that "objects in rest stay at rest, and objects in motion stay in motion with the same speed unless an unbalanced force acts upon it." Translational equilibrium occurs when the sum of the forces acting on an object are equal to zero. With this information, it was possible to solve problems pertaining to forces.

What I find difficult is knowing where to place theta on a FBD sometimes. If the object is on a slope, it makes placing theta in a FBD harder. Also, if the object is moving to the left, as opposed to the right, I sometimes forget to make the numbers on the left of the origin positive instead of negative.

My problem-solving skills are average. I feel like I sometimes get impatient if I can't figure out how to solve a problem, which is sometimes frustrating. I do, however, feel confident in drawing FBDs, aside from determining where theta is occasionally. My weaknesses include solving problems that I do not know how to start and being impatient. I also feel unsure when to use certain equations. I do feel though that I can solve most problems accurately.

Part B:

What we have studied can help in various situations in the real world. If someone is involved in architecture, they will find what we have studied handy when constructing bridges. Also, when attempting to pull a wagon that does not budge, you can figure out how much force to exert on the wagon. Also, it is possible to figure out the tension force in a hanging stoplight. There are many ways in which what we have studied can be applied to the real world.

Content: Voki 2

This is my second voki...

Content: Projectile Motion Glogster

This is an explanation of projectile motion...
http://kiral.glogster.com/Projectile-Motion-Without-Angle/