Mass and Newton's 1st Law

Physics homework for 11/19/14:

Inertia and Newton's 1st Law

       Today in class we mainly watched "Eureka" videos about inertia and elements related to it. We also took notes, read from the book, and had a little discussion. 

Now, I will give three examples in my life that show the correlation between inertia, Newton's 1st Law, and how massive something is:

1). When I was younger and living in another location in MA (Woburn), I used to live in an apartment complex and at that complex I used to roll down hills for fun (sounds crazy right? It definitely explains a lot). Either that or I'd ride down a hill with my bike. Any ways, I remember whenever I rolled my bike down the hill on its own it would always roll quite fast, but whenever I was on it it was a little slower going down the hill. Also, I usually stopped at the bottom of the hill on my own, but if I was on my bike I would keep going down the hill onto the grass and down towards another hill sometimes! And I did not change my speed either, though inertia is not dependent on speed so we need not worry about that. This situation shows inertia because with more massive objects (it being me on the bike here) there is more inertia. If there is more inertia then the body will have a hard time changing its current state of motion because the greater the inertia, the greater the tendency an object will have to keep doing what it is doing! And that is what happened here, the bike and I were in motion BUT it was harder to stop us in comparison to just me rolling down the hill which was easier to stop. I have less inertia than the bike and I combined. You'll notice how more massive objects are harder to move AND to stop. Whereas less massive objects do not have that problem as much. The amount of mass affected the inertia and how fast the bodies would stop and start, as a result I continued going longer on my bike than by myself.

2). Or, sometimes I need to move things around in my room like my bed or my chair. When my chair does not have a massive backpack on it it is extremely easy to put in motion, whereas it is harder to push my bed into motion. These objects have and show inertia because they are so lazy I gotta move them! Nah, the real reason why is because with inertia an object at rest will stay at rest or stay in motion; the body wants to do what it is currently doing, and since both my bed and chair are at rest they will stay at rest because they are stubborn as hell. Here, the big mass for the bed (especially with the dense mattress and iron bed post) affects how easy it is for me to get it out of rest. It takes a bit of force for me to really move it, but the chair is so much lighter; less dense and massive, so I can push it with ease and without having to go to the chiropractor's (I fall a lot--DON'T JUDGE MEEE). 

3). And finally, I don't know if this counts, but when I turn off a fan in motion it usually does not come to an instant stop. Whenever I hit the treadmill in our little extension room I usually need to turn on the fan and open the door just to stay cool (not that I don't already look cool [l i e s]), and I set my fan on the highest setting. But when I stop it, it takes a few seconds for the blades to stop spinning. The blades represent inertia by not stopping its course of motion just yet. The fan is quite massive, especially at the bottom, so it is definitely hard to move due to that AND the blades don't stop instantly because with more massive objects there is more inertia therefore it is harder to get the blades out of motion. The state of motion before I turned the fan off was not in rest, so the fan had the naturally tendency to want to stay in rest but was stopped by me and the surrounding forces around it.

BONUS: 4). I see many vehicles on the roads nearby every single day, especially since the bridge is right down the street for me because the intersection is close, but I've seen many vehicles zoom by and when the red light flashes I notice that smaller vehicles are easier to stop than bigger ones. You can see inertia in such a situation because the big vehicles have a larger tendency to stay in motion than the smaller ones due to their huge mass! The bigger vehicles did stop, but they jerked forward as well before stopping. But the smaller vehicles probably stopped a little faster due to their smaller tendency to stay in their current motion. Both vehicles demonstrated their inertia by how they preserved their state of motion. 

5). Whenever I drop cereal (:-((( and lose my breakfast) the cereal usually falls down onto the floor but then stops immediately, on the other hand, when I drop something like coins (not the chocolate ones; it's not Easter yet, guys) they take a while to get back to rest. The coins show great inertia because in their motion they try to continue it by spinning and scattering on the floor once they fall, but the cereal just tumbles onto the ground and stops. The mass once again makes the objects stronger in their preservation of motion or weaker.

More force is needed for more massive objects, and the mass matters, not the SIZE/VOLUME. Focus on the mass like 5 kg and ignore everything else because inertia is dependent on mass.

All of these examples tie to inertia, Newton's 1st Law, and mass because the mass of the bodies mentioned affected the inertia of the objects and inertia is related to Newton's 1st Law due to the fact that Newton's 1st Law relates to an object's constant or resting motion. 

Inertia Investigation

Physics homework for 11/17/14:

Investigating Instances of Incredible Inertia

       Today in physics we focused on inertia and we learned about Newton's First Law of Motion. To learn about these things, we rotated around from stations and did investigations. Though I would love to summarize everything we did today, I will just explain what inertia is and what Newton's first law is.

So what is inertia?--

Person I don't know: IS THIS INERTIA!?!? :DDD

Yes :D, well, it is one part of it, but yes ;w;.

Inertia is the tendency of an object to preserve its motion unless acted upon by an unbalanced force. It is also the tendency of an object at rest, any object at rest, to stay at rest OR it is when an object in motion stays in motion with the same speed, in the same direction (when the forces are balanced) unless acted upon by an unbalanced force. And that definition also is what Newton's first law (AKA "the law of inertia") is. Inertia can be found in any body as long as the body is acting relative to the definition of inertia and can only occur when the forces are balanced I believe. 

And just for fun, I wanna try my hand at an explanation of Newton's first law for a first grader, "Newton's first law" is when an object that is not moving does not move unless something else makes it move like a person. Or it is when something moving keeps on moving in the same direction with the same fastness unless something stops it from moving in the same direction and speed. 

Okay, now onto some examples of inertia!~

One instance of inertia in my own life and through out my days involves swirling milk. The details behind this situation basically involve me being super tired and wanting to make coffee with milk. After I heat up the milk I of course need to pour in the sugar and coffee mix and when I want the solutes to dissolve I use a spoon to stir the solutes into the solvent. Of course the sugar and coffee will be distributed nicely, but also when the spoon is pulled out after mixing everything in the solution still continues to swirl around on its own! I believe that is a form of inertia, especially since the coffee seems to swirl in one direction over all (counter-clockwise or clockwise depending on which way you stir the solution) and since the speed seems to remain the same until the end (at the end the coffee loses its momentum and goes back to staying at rest). The coffee stayed in motion even after I stopped swirling it around and it only stopped due to some other force (I'm guessing maybe inertia is the reason why it goes back to rest too?) I gave the coffee some applied force, the coffee had inertia, and it was affected by some unbalanced force causing it to go back to rest.

Also, I do not know if this counts as well, I feel like these are not good examples; but when I am taking the MBTA or the T and I am on the bus I am usually at rest through out the whole trip, especially if I am sitting down. Even though the bus is moving, I might jolt a bit at first or during some intervals but I am mainly at rest. Now, when the train or bus stops suddenly I kind of jolt forward but go back to my original position at rest after. That represents me having inertia because with inertia an object at rest will stay at rest unless acted upon by an unbalanced force. Technically, the force from the train/bus must have made me jolt forward, but I sprung right back to rest after. I had a tendency to stay at rest because of inertia (nah, it's mostly laziness and sleepiness actually).

My last example involves two different scenarios; one where I move my tiny little Play-Doh with items on it around and another where I move open these drawers in my kitchen to get bowls and what not (to get fat, of course). So, when I move my little table the table is obviously in motion but not all of the contents on it; in fact, only one item is staying still usually. Today I had a few water bottles, money, a banana, and my pencil pouch on it and only the banana stayed at rest when I moved the table. That might be an example of inertia as the banana stayed at rest. Maybe the force from my hand and the table movement was not strong enough to move the banana? Maybe inertia just helps certain bodies stay at rest? Well, all I know is that I am hungry due to this talk about fruttas. And when I am in the kitchen moving the drawers open, the contents in the drawers remain at rest even though the drawers move due to inertia. The objects are not really being affected by any force and are staying at rest.

Oh, and me sleeping is of course an example of inertia :333 (TwT). 

Welp, I must do the homework of the history class now, I will see the people of this Earth in a few hours! Good nighteth :DDD.

HAVE ALL THE FLUFF <3 YES <3 (more luff will help le world hopefully :33 <3 )

Balanced and Unbalanced

Physics homework for 11/13/14:

Balanced or Unbalanced?

Today in class we mainly worked on white boards and drew more FBDs on them! We did not take many notes, we just redrew what we drew during class and discussed topics. We also got a little work sheet as well. Before I get into the main part of the post, let me explain what a balanced force is and what an unbalanced force is, we learned a lot of other things today too, but balanced and unbalanced is what we are really worried about here. 

A balanced force is when two opposing forces when added and/or subtracted equal zero. Balanced forces have a net force of zero and are equivalent. A balanced force, for example, is gravity downward with a magnitude of 5 and normal force upward with a magnitude of 5. They are both the same so therefore when subtracted they equal 0. Forces can also be broken up into separate lines on certain sides I believe so you must count even Newton on one side. Balanced forces usually keep an object at rest.

An unbalanced force has a net force that does not equal zero and cause objects to move usually. These forces are not equivalent; they have different magnitudes. Also, keep in mind we're talking about opposing forces. An example of unbalanced force would be 10 N up and 5 down. The net would be 5 which of course does not equal zero. Therefore it is an unbalanced force. Think of scales when you hear these classifications.

 Let's begin with an unbalanced diagram. This FBD has four forces acting on it as you can see (normal, friction, gravitational, and applied). The first force that we always label first, gravity, is the force going downward and is the force opposing normal force. Normal force comes after that as the item is probably on a surface and must oppose gravity (also probably because the object is not accelerating downwards). Both normal force and gravitational force are equal in magnitude here. So why is this diagram not balanced? Well, the reason why is because even though the net force of gravity and normal force is zero, there are two other forces that have a net force that does not equal zero; friction and applied force. The applied force is the force going right and friction is going in the opposite direction as with all opposing forces. Both forces have different magnitudes though as the arrow length indicates. Since they have different magnitudes there will be a net force, and balanced forces have a net force of zero. Even though only one set off forces has a net force, the diagram is still unbalanced. Really what makes this unbalanced is friction and the applied force and the net force will cause the object to move most likely. It is the difference in magnitude and the opposing directions that cause it too. Unbalanced diagrams will have non equivalent magnitudes with opposing forces basically.

This is a balanced FBD. But before I explain why, I shall describe the forces acting on the body above. The forces here are friction, applied, gravitational, and normal. Each force is of the same magnitude, the only difference is the direction each force is going. Gravity is going down, normal is going up, applied is going right, and friction is going left. Since the object is balanced it is at rest. Now, since the forces are of the same magnitude there is no net force when subtracted and when the net is zero it is balanced. And each opposing set of forces are the same size, due to that this is balanced. And it does not matter if the forces were broken into two arrows or something, if the magnitude when added up for one side is the same it will still work as the same amount of force is being applied.

Good night everyone, I suck but have bunnies <3

Free Body Diagrams

Physics homework for 11/12/14:

No. That's not what a free body diagram is; let's clear up what a FBD (free body diagram) is.

And let's also hear about what we did in la classe today in this little extra section. This section won't count towards the main part of the blog posts and will just help support and clarify certain aspects of what I am explaining. But since basically only my classmates and teacher will be reading my blogs, I don't need to really explain everything again, right? I would like to reiterate though, just to recap and what not.

Today in class we drew many free body diagrams based off of different scenarios and discussed FBDs. We also went into unbalanced and balanced forces more towards the end through a reading (pg 167 I think?). Also, we focused on certain aspects and learned some new things about the forces so that our diagrams were accurate. For example, we learned about scenarios where things are thrown and we focused on normal force in relation to acceleration and what not. Really, a lot could be reviewed from class but I won't touch it and let it be, especially since it is not really needed as much here. 

Now, what is an FBD/free body diagram? No, it is not a diagram of free bodies of people and what they look like. A free body diagram is a visual representation of all of the forces acting on a single body portraying each of the forces' magnitudes and directions in a given situation. Or simply put, it's a good way to show your situations involving the forces through pictures and it shows what the forces are like and what they are doing in that diagram based off of a specific situation. It is a good tool to help in better understanding and representing the forces and has many other purposes as well most likely. Not all forces are in FBDs, though in some many forces are shown. With FBDs you must properly follow along with the details of the scenario you are assigned and you must properly label and draw everything. Size your arrows correctly and from the center of mass. Label gravity first as a tip if gravity is appropriate according to your scenario. Also, draw one object; the object being focused on and mentioned. Sometimes various objects are involved, but pay attention to just what the description says and is talking about, then go from there.

So now do you understand what a FBD is smart cookies? :DD Not that you needed that explanation :33.

Person: Is it this? 

 That's... Better? (No, it's definitely not a FBD, sorry :-(((().

 

Here are the links I used: http://www.physicsclassroom.com/Class/newtlaws/U2L2c.cfm#1 and http://www.physicsclassroom.com/Class/newtlaws/u2l2c3.gif

The FBD above was drawn based off of this scenario from the website I got the picture from: A girl is suspended motionless from the ceiling by two ropes.

The object in the free body diagram is the girl that is mentioned in the scenario I pasted and the girl is represented by a box which most bodies are usually always represented by. While we have not really drawn and/or discussed diagrams with tension force as much it is very easy to understand and is good to be exposed to.

The object here is not moving on its own or at all; the description states the girl is suspended motionless. The girl is just hanging from a ceiling by two ropes and will not be in motion until something causes motion like a force or like energy (even air possibly). 

While the girl may not be moving, there are still forces acting on her just as upon us. And--*hears Ms.Reid's voice echoing throughout my head saying "what's the first force we always label?"*--s-sorry... And the first force we always label is the force of gravity. Gravity is probably in every single FBD UNLESS the details state otherwise (sometimes the scenarios may occur in a vacuum or in space so gravity won't be acting on an object there most likely but that's a different topic). Fg (gravity) is present here and is the force in the diagram with a magnitude equivalent to that of the opposing force in the diagram. Gravity usually always acts downwards on an object like it is here on the girl and it is what is keeping the girl not near the ceiling, but hanging from it (well, the ropes technically are suspending her, but the strength of our gravity keeps her from floating). Gravity is pushing her down, but not enough to make her fall to the ground luckily and notice that there is no F(N) (normal force)--why? And why is she not falling to the ground then?? Or why is she motionless?? Well, the girl is in the air, not on a surface of some sort where normal force would be in action perpendicularly so there is no normal force and while we know normal force keeps objects from accelerating downwards other forces can also help balance out other forces and can also help keep an object up (balanced forces in general are the reason behind some objects not accelerating and this diagram is most likely balanced). Tension force is that force in this diagram, and it is the only other force acting on the elegant swan dangling from the ceiling. Tension force here has a similar magnitude in comparison to the gravitational force, and is thus keeping the girl from falling entirely.  Tension force is acting upwards, opposing gravity in equivalent amounts and is really coming from the ropes.Yeah, expect a lot of suspension and roping when tension force is mentioned; that's usually where it comes from. And all though tension force seems smaller than the gravitational force it really is not and is just broken up into two pieces because there are two ropes. Besides, if the girl is motionless the forces around her MUST be balanced from what I know, I believe there are exceptions for certain scenarios but here it most likely needs to be balanced. My only constructive criticism toward the diagram would be how tension force still looks smaller than the gravitational force, but nonetheless is pretty good. 

Lovely diagram, eh? Poor girl :((.

And I should make it clear that she is not up close to the ceiling, if she's hanging from the ceiling then gravity must be stronger than the tension causing her to hang, but there is still enough tension force to keep her partially up in the air. It makes sense since the net force would cause the girl to be either closer up to the ceiling or farther down because with net force usually an object is not at rest. (Wrote this earlier, DO NOT make this mistake. I believe I was wrong here).

EDIT: The opposing forces are actually most likely balanced here because if they were not the girl would be accelerating downwards which she is not doing. Maybe gravity is stronger than the tension force somehow and that is why she is hanging from the ceiling, but at the end of the day she was motionless and that was because of the balance between the forces. There was no net force. If she was motionless, she had to have been balanced technically. I cannot edit the paragraph above at this moment, but keep in mind that what I wrote above is not 100% accurate. Sorry. The only reason why she is dangling from the ceiling is because the ropes are keeping her at that position now that I realize it. 

And a little conclusion: Forces for me has been the hardest strangely, not unbelievably hard, but moderately tough. But, I will probably ask for help soon and look wherever I can to clarify things.



(Technically honors physics but close enough @w@). (Irrelevant but very true and explains everything about me *cries*).

Also, I accidentally searched "Fapp" while on Google Images to look for applied force..
Needless to say I sincerely regret that and need to drown myself in bunnies for the next three hours. Good night ;w; <3 . (Kidding, but seriously guys don't EVER search "fapp" good gravy on goose ghosts it will be fghdfgf- DD:)

 YES, NOW STARE INTO ITS SOUL OR FOREVER HOLD YOUR PEACE MWUAHAHHAHAHA

sorry, i love bunnies a lot bye bye ;w; <3 

(Note: Anything in italics or bold probably are not major details, though they do help a bit. The main meat is the normal typed words).

Vector and Scalar

Physics homework for 11/7/14:

Friday, November 7, 2014

“Vectors & Scalar” Blog Post

Explain the difference between vector and scalar and find an example of each that we did not cover in class (you can use the internet or pull from your own life)

Vector and Scalar: The Difference and Examples of Both

             Yesterday in class we learned about vector quantities and scalar quantities, two types of classifications for variables such as mass and distance. We also drew vectors and learned how to add vectors (by the way, if that is confusing to anyone I suggest either asking Ms.Reid or someone else for help  or go to Khan Academy as there are a few videos about vectors and scalars, that is where I first learned about vectors and scalars in fact). We also took some notes as usual and took a little clicker quiz at the end to test our understanding of the topic. I remember only getting weight wrong, but gladly I understand why it is a vector and not a scalar. 

Okay, so I keep on saying "vector" and "scalar", but what do those words really mean and what are they? Are there any differences between them? Well, both are types of quantities and certain variables fall into each classification like time, weight, velocity, etc. All quantities I believe are either a vector or a scalar. A scalar quantity (e.g. distance, time, mass, speed, etc.) is a quantity that is fully described by a magnitude/size (or number) without anything else. Whereas a vector quantity (force, weight, velocity, acceleration, etc.) has magnitude as well as a direction like left, right, up, down, etc. So the only big difference is one has direction (vector) and the other doesn't (scalar), the only similarity is that both have magnitude.

You can identify either one of these quantities by looking for numbers and/or directions OR if you want to know if a quantity is a vector or a scalar, then think about its definition and what goes with it. For example, acceleration is a vector quantity because it is a "change in velocity (speed or direction)" and velocity is a vector itself so you can probably identify other vectors this way. 

Also, with vectors and scalars you can apply mathematical operations (most I believe) to find the net or the resultant (the net is the result you get after and usually it is after addition or subtraction). We learned how to add and subtract vectors a bit to find the resultant vector, but I won't explain that. Khan Academy will definitely help if you need it though! : https://www.khanacademy.org/test-prep/mcat/physical-processes/vectors-and-scalars/v/introduction-to-vectors-and-scalars

Okay, so now let's add some examples of both!~ I'll take one from the web and one from my life.

Well, I know temperature must be a scalar if you measure the magnitude and not the increase or decrease. Many people say it is a scalar and it most likely is as we measure the magnitude of temperature, not the direction. And temperature is all around us. Literally! I mean, I have a body temperature, my house's thermostat has a high temperature since it is winter, and New England cannot make its mind up about whether it wants to be hot or cold. :-(((( Also, I believe just about everything has a temperature since all atoms have kinetic energy, is that correct? Sure we don't measure water bottles, but no atoms are at absolute zero either (most likely). 

And momentum must be a vector as it has direction and size. Also, the formula involves a vector quantity. Before I give an example of momentum, let me give the definition of momentum. Momentum is the amount of motion occurring in something that is moving, or the force that drives something forward (or whatever direction) to keep it moving. The best example I can give is of a huge truck rolling down a hill and a little truck rolling down a hill as well. Apparently one of the trucks will have a greater momentum due to their mass and velocity and I believe gravity plays some kind of a role here. But the objects have some kind of a momentum which involves a number and a direction. In this case it might be some number and going down hill.

There are a lot of examples of these quantities, but for now I will just leave it at that. And it is good having two different classifications of quantities as it can help us understand quantities better and as it can help us measure things better as well as a lot more.

Any ways, buenos morning and hallelujah pancakes and waffles!

B)))))).

Four Forces

Physics homework for 11/6/14:

Thursday, November 6, 2014

"Four Forces" Blog Post

Describe each of the four types of forces that we did in class in your own words.  For each one, give the description and an example of it in your life

Challenge for Ooviya: Write your blog post in a few sentences, dammit! 

Four Forces and Examples of the Forces

           Today in Ms.Reid's class we learned about the four types of forces; tension, applied force, gravity, and normal force. In my own words, I will describe these forces and then go into what we did today after.

          In my own words, gravity, the force we all especially know of, is a non-contact force (a force that does not need to be in direct contact with a body) that pulls objects towards an object with a greater mass than the objects being pulled in. It is a force that attracts bodies to each other and a force that attracts bodies toward any other body having mass, and on Earth gravity attracts bodies towards the center of the Earth and keeps us grounded (it also causes objects to fall when dropped). 

Now, I might not describe the other forces as well since I am not too acquainted to them, but doing my best in describing applied force, I believe applied force is a contact force (a force that needs to be in direct contact with a body) that is acted upon/caused by an object by a person or another thing like a person pushing a door open. 

Next, normal force is a contact force that is the "equal but opposite force" from one of Newton's laws I believe and it is usually pushing up. It is also perpendicular to the surface an object is resting/moving/etc. on and it counters an opposite force which allows an object to stay still. 

Finally, tension force is another contact force that pulls and is probably transmitted through a rope or cord of some sort. 

Here are examples of each of the four forces in my own life! :

--Tension force (FT): Whenever my mouse that is connected to my computer's USB driver falls off of my bed it does not touch the ground because it is still attached to my computer's USB drive and because of tension force; there's a pulling force that keeps it from falling and gravity actually makes my mouse fall off of my bed whenever it gets pushed off and gravity would make it fall straight to the ground if it were not for tension force. The cord probably does most of the work, the tension must be in the cord and the force must be sent throughout it which in turn keeps the mouse from dropping to the floor.

Or think about pulleys, swings, ladders, masts, tug-of-war, etc. Maybe not all of them have tension force, but think of strings and ropes when you hear "tension force."

--Gravity (Fg): I rolled off of my bed once oh so elegantly like a beautiful, graceful flamingo without realizing I was super close to the edge and--BAM--HEAD PAIN :-(((. Thanks, Obama--I mean gravity. Yeah, gravity is the reason why my head hit the ground and why my body fell to the ground and did not majestically float as I had hoped it would. Earth's gravity attracts me to the ground because of my tact (just kidding, my tact is non-existent, I'm an awkward penguin for Christ's sake!)

--Normal force (FN): So when I am on the scale checking my weight normal force is being applied on me because if it weren't I would be falling through the ground to the center of the Earth. While gravity is pulling me down (:-((( like it always does, ugh, always putting people down), normal force is pulling me up and it usually always pulls up to offset an opposing force which in turn keeps an object at rest or at least not careening through the ground. The force is perpendicular to the scale and if I weight 110 lbs, gravity would apply 110 N down I believe and normal force would apply 110 N up to make sure I remain still. 

Or picture items on a table, especially things that you stand up and try to keep still.

--Applied force (Fapp): When I push the exit doors open to enter into a place like a fool--bad ass I am applying applied force (OOOH, I GET IT NOW *REALIZATION*--don't worry I don't use the exit doors). The reason why is because applied force is a push or pull caused by a person or thing and in this scenario I am pushing or pulling an exit door/enter door open to get in or out. 

Or imagine pushing your iPhone off of a table :-))) the beauty is unbearable (just kidding, sorry if someone had a heart attack reading that). xD Oh boy. 

Extra section!:

I don't know too much about the forces in general, but I'd love to gather more information about them and learn about them :D. 

(Fun fact: Newton actually did not get hit in the head with an apple, he observed an apple falling and knew of and about the concept of gravity beforehand!)

Also, the four forces are either weak or strong or something else (electromagnetic and gravitational I believe) and gravity is a weak force from what I have heard. 

I could try and go into a lot about the forces, but for now I will mention what we did in class today. Today we took notes and did four stations to get an idea of the forces. A force in general is an interaction between objects that causes an acceleration. Each force has its own abbreviation with a capital "F" and a subscript. Some forces are contact forces, some are not. But today we were solely introduced to it all.

:333 Arrivederci a domani~.

*SNORTING MANIACALLY IN THE BACKGROUND*