Unit 1 Blog Reflection -- Sept.

Part A: 

I learned about *Newton's 1st Law of Motion (Inertia), *Net force and Equilibrium, and *Speed, Velocity, & Acceleration. The three topics cover a lot of material. 


Newtons' 1st Law states: An object at rest or in constant motion in a straight line will remain at its current state unless a nonzero outside force acts on it. To put it simply, an object will continue to do what it's doing unless something acts on it.

Inertia is not the reason why things keep doing what they're doing; it is not the reason why an object moves or stays at rest. (These objects just do what they do until a force acts on them).

For example: I learned more in depth about why a coffee cup will fall straight down on the ground when the truck bed that it's on quickly moves. The cup is at rest on the truck bed; the truck moves; the cup is still at rest when the truck moves; the cup falls straight down because the force acting on the cup is not big enough to move it. Friction and time are minimal. The outside forces in this case are the truck moving and the friction between the cup and truck bed.

Net force and Equilibrium: Force is measured n Newtons. A net force is when more than one force acts on an object. Equilibrium is when the net force is equal to 0N, or no net force.

If a box is being pushed 5N to the right while at the same time being pushed 10N to the left, the net force is simply 10 - 5 = 5N.
If a box is being pushed 100N to the right while at the same time being pushed 100N to the left, the net force is 100 - 100 = 0N. (Equilibrium).

An can be in equilibrium in two circumstances: The first is when an object is at rest with no forces acting on it and the net force is zero. The second is when the object is moving at a constant speed while the forces acting on it (from both the left and right) cancel to zero Newtons.


Speed, Velocity, and Acceleration: Speed is the amount of distance a moving object covers over a certain time interval. Velocity is the amount of distance [with direction] a moving object covers over a certain time interval. Acceleration is a bit different. Acceleration is when a moving object covers the same change in distance [with direction] over a certain time interval. ~ Here are the equations!

Speed = distance/time
S = d/t

Velocity = distance with direction/time
V = d/t

Acceleration = change in velocity/time
A = ∆v/t

Speed is not interchangeable with velocity. Velocity must have a direction. If an object is moving at constant speed, it might not be going in a set direction. If an object is moving at constant velocity, the object must be going at an unchanging speed in an unchanging direction.

Constant velocity vs. Constant acceleration --
*Constant velocity* is when an object is moving at an unchanging speed in an unchanging direction.
*Constant acceleration* is when an object covers the same change in distance [with direction] over a certain time interval. The amount of distance covered increases or decreases by the same number of m/s^2.

The definition of acceleration is ∆v/t. An object cannot be moving at constant velocity and constant acceleration at the same time! The velocity must be changing for there to be an acceleration at all.

If the velocity is changing: the object may be speeding up, slowing down, or changing direction.
If the acceleration is changing, the rate of change of m/s^2 will not be regular,

EX: After 1 second, an ball's speed is 5m/s. After 2 seconds, its speed is 10m/s. After 3 seconds, its speed is 15m/s. What is the object's acceleration? (Hint: A = ∆v/t). A = 5m/s²

The "how far" equation helps calculate how far an object has gone when it is moving at constant acceleration.
D = ½at²

The "how fast" equation helps calculate how fast an object is moving when its acceleration is constant.
V = at

In the example above, how far will the ball have gone after 5 seconds? How fast is it moving after 5 seconds? To do this problem correctly, we must write out the equations first. We use the 2 equations above. Make sure to write the problem neatly and with the correct units!

V = at
V = (5)(5)
V = 25m/s

D = ½at^{2
D =} ½(5)(5)^{2
D = 62.5m}

Graphs and Lines: When we have many distances and times, we can create a table to organize the data. The time goes on the x-axis and the distance on the y-axis. In excel, a graph shows the speed, velocity, or acceleration of an object depending on the lab experiment. 
Once a trendline is added, the equation of the line is shown. We can see that the number multiplied by the "x" [or just the "m"] in the equation is the slope. *(Y = mx + b)*. 

The equation D = ½at² is applicable to this concept...D is the "Y", ½a is the "m", and t² is the "x". 


~ What I've found difficult about each of these topics is how confusing it can sometimes when the equations and terms get mixed up in my head. Also, I ask myself relevant questions about the material but end up going too far off the course of our study. What can I say...I'm curious! I believe I missed some content in my post, but it's hard to add it all in!

~ I overcame these difficulties by asking my peers and teacher about how I can better understand an grasp the concept of this unit's material. My lightbulb clicked when I realized how knowing real-world situations involving physics can help me see it in a new light. 

~ My problem solving skills are top-notch; I am in AB/AP Calculus this year and have a ton of practice with equations, graphs, and math-related things. I attack physics calculations with positivity, thoroughness, and perseverance. 

~ My effort towards this class from my point of view is strong. I enjoy learning and helping others even when I feel hopeless. At times, because I've taken a physics course before, I zone out in class when we are learning things that I have previously mastered. I do my homework when I can, fully and carefully. Honestly, at first, the thought of blogs was terrifying and silly, but now I kind of like being able to share my thoughts and study at the same time on my awesome blog. 

~ I try to be creative on my blog so readers/viewers are engaged. Answering the questions for this review post reminds me of my confidence in learning physics. As mentioned before, I have taken a physics course before, but now I am somewhat skeptical about the material such as electricity and magnetism that I have no clue about. But my peers are also nervous too, so that's okay. My communication seems to be fine - I ask questions in class and discuss problems with my peers. So far, the Juniors in A-block are welcoming and don't act weird around me because I'm a 6th former. Yay!

~ My goal for this next unit is to deepen my thinking and participating in and outside class. I want to continue to do the things I do and be successful. If I have time, I want to make use of Conference Periods. Hopefully Ms. Lawrence will be lenient if I am a little late or do not have my homework completely finished. I intend for this not to happen though.


Part B: 

The connections between physics and the real world are completely parallel. Because physics is a branch of science dealing with how things work, I see everyday examples outside of class. The coffee cup and truck bed, the hovercraft, riding in a car, equilibrium at rest, and more!

Here is the video podcast my group made for this unit. We were assigned to Inertia. 





I'm excited for the next unit,

CHEERS.

Constant Velocity vs. Constant Acceleration -- Lab

The purpose of the Constant Velocity vs. Constant Acceleration Lab was to understand and see the physics concepts in real-life and to experience what we're learning first-hand. I have done this lab many times before, but it was still really fun again this time!

Constant velocity is the same distance covered in a certain amount of time. The speed is unchanging. Constant acceleration is the same change in a distance covered over a certain amount of time. The two terms are not interchangeable.

My partner and I set up the lab with a long table, a piece of chalk, and a metal ball. We set a metronome  for 0.5 second intervals. Next, while my partner rolled the ball, I quickly drew chalk lines every 0.5 of a second wherever the ball was on the table. Once we measured the distances, we filled in a data table to record our findings. The second task was to do the same experiment with the table on an incline. Using two books, two table legs were supported and raised. The data was recorded.

*Constant velocity is when an object remains at an unchanging speed. In the lab, the chalk marks were equally spaced apart, meaning that the ball was rolling at a constant velocity.
*Constant acceleration is when an object speeds up or slows down at the same rate for each time interval. In the lab, the chalk marks were spaced further from the mark before it, meaning that the ball was rolling at a constant acceleration.

Constant velocity is the same distance covered per amount of time. (V = d/t)
Constant acceleration is the same change in velocity per amount of time. (A = Δv/t)

The graphs of constant velocity looks like a straight line with each point equal in distance from the rest, whereas the graph of constant acceleration looks like an upwards curve with each point further from the previous one.

The graph's equation was given on Word when adding a trendline. Y=mx+b is the equation of a line. "Y" is the meters, "X" is the seconds. "M" is the slope. The how far equation, d=1/2a(t*t), parallels this concept. 1/2a is equal to the slope. To find "a" one must multiply "M" by 2 or divide it by 1/2. 


I LEARNED:
1.) What units to put in each axis and how to plot a scatter graph.
2.) How 1/2a is the same as the slope "M."
3.) How to think about mathematical physics in real life, mainly how it changed my perspective.

CHEERS.

Vel vs. Acc -- Resource

This youtube video is about distance, velocity, and acceleration. It is short...about 3.5 minutes, and easy to understand.

First, the guy who explains these concepts includes almost every simple description of each term, and provides a real-world example. Graphs are shown to help see what "constant" really means.

What I think are helpful, are the equations that we'll use when determining the constant velocity or constant acceleration of an object. 

Velocity is the distance/change of position per amount of time.

V = d/t

Acceleration is the change in velocity per amount of time.

A = Δv/t

*The terms are NOT interchangeable! 

*The definition of constant acceleration states that it is the same change in velocity over a specific time interval. The definition of constant velocity states that there is no change in velocity over a specific time interval.

*A constant velocity cannot also be constant acceleration, because the velocity cannot be both changing and un-changing at once. 

CHEERS.

Hovercraft Post -- Descriptions & Ideas

A.) Riding the hovercraft feels like sitting on a rolling skateboard that is above the ground. I would say to others to definitely expect somewhat out-of-control. The hovercraft won't stop unless unplugged or someone holds it stationary. Riding a skateboard, bike, etc. is different in the fact that friction is absent when the hovercraft glides, whereas a skateboard slows because of the road it rolls on.

B.) I learned that (besides the definition of Newton's 1st Law) that something can be moving and not have any forces acting on it. Also, the more/less weight, the more/less inertia. Equilibrium is when an object's net force is zero.

C.) Acceleration depends on the weight of the object and how difficult it is to exert a force on the object. When being pushed or pulled, an object is accelerating, but as the hovercraft reaches its maximum speed (constant), it does not accelerate.

D.) Based on the hovercraft, constant velocity is attained when the object is moving, but in equilibrium as well. The net force is zero, which means the hovercraft is no longer moved by a force, but by inertia and the continuation of its current state.

E.) Some classmates were harder to stop than others because of their mass. When an object (or person) has more mass, more force must be exerted to start/accelerate, and to stop. This is part of Newton's 2nd Law I think.

CHEERS

Newton's 1st Law -- Inertia Resource

"Every object continues in a state of rest or of uniform speed in a straight line unless acted upon by a  nonzero net force."

Newton's First Law of Motion is Inertia. This resource diagram helps explain how Inertia can be seen in everyday life. The tablecloth trick is well known. One must pull the cloth off the table without the dishes falling.
Because the cloth is pulled quickly, the force of friction only exerted for a short amount of time, allowing Inertia to do it's thing: remain unchanging. (If done successfully), the dishes will remain on the table as they are.

I love this example.

http://www.wired.com/wiredscience/2010/10/mythbusters-inertia-and-friction/

The source is a mythbusters article that explains the difference between Inertia & Friction. It cleared up a bit of confusion for me. One thing that I specifically like is the correct diagram. It is relevant to what we are learning:





I apologize for not having a happy video, but this article could not be "embedded" so I have a lousy URL instead.

CHEERS

Introduction Post -- Day 1

STARTING OFF: I am excited to be in a class section with 10+/- other Juniors. A class of people not in my form is refreshing, and I'd love to be an honorary Junior, if you'll have me.

Learning Expectations: I have previously taken "physical science," (8th grade) which gave me an overview of what I expect to learn and understand in this class. I'm super ready to dive in to the material; I'm a bit of a science freak. 
A few things that I really want to cover this year: Newton's Laws; Light/sound waves; Thermodynamics. I like the concept of force and its relationship to objects. Light waves, sound waves, and color are other topics that I would like to study. Thermodynamics is my absolute favorite part of learning physical science.

Importance: Physics is the study of the surrounding world; it concerns matter and energy within almost everything. I think, (my opinion) that studying this branch of science can help an individual understand and apply real world situations to their life. Knowing how and why things work/act the way they do is beneficial to anyone, even if they're not interested in the subject.

Questions: Will we be doing experiments, and will these experiments/projects be heavily weighted on our grade? If my experiments don't work or function properly, will I be penalized? Will we be learning about Thermodynamics in this course? What is your (Ms. Lawrence) favorite chapter/topic to teach? Will our entire course be "online"?

Goals for Physics this year: To live and learn alongside each friend/peer in my class; To leave AS feeling fulfilled and content with how I mastered the material; To take in each topic separately but cohesively and with a positive attitude; To enjoy Physics.

-- Physics Friends: If you feel the need to comment, do so in style.

CHEERS