Elastic vs. Inelastic

Do you know what elastic collision and Inelastic collision is? So if you don't know I will explain to you what each collision means and how both are different. 

Elastic collision- this collision is when two objects/people collide and they "bounce" off each other 😉

Inelastic collision- this collision is when two objects/people collide BUT "stick together" 🙄

Well if you don't understand with the definition I'll give you an example; 

                         EXAMPLES;

     Elastic collision: An example of this collision in my life is when I play with a bouncy ball. I would rewind the ball to the wall and the ball would "bounce" off the wall back to me. This is an example because the wall and the ball are colliding but the ball is bouncing off. 🏓👌🏼

Inelastic collision: An example of this collision in my life is when I was playin around with my bestie 👭 and I threw myself on her so I could pick her up and we stayed stuck together that I fell down with her on the floor. 😂😅 but she didn't get mad. In this example the part of me falling in the floor with her is the Inelastic collision because we collided and we stuck together that we BOTH fell down.😝

Now if you still don't understnd hea r pics 

      Elastic Collision; 👤👤

          Inelastic Collision; 👥

Elastic Collisions

What is momentum? Well, if u don't know what it is I can explain it to you. Momentum is the force times the speed of an object. And you can compare momentums between objects. 

- What has a greater momentum; a train at stationary or a moving skateboard...

    Of course, the moving skateboard has a greater momentum.  You must be asking " but why if the train weighs more than a skateboard?" Blah blah blah... Yes it's true a train weighs more but in this case when you want to find momentum you need the objects force (kg) times the objects speed (m). So, the train is at rest which isn't moving and the skateboard is moving. So, in this case the skateboard has the most momentum because it's moving a weight. And the train is at rest not moving at all which isn't doing work for train to move its weight. 😃👌🏼✏️

Work vs Power

The difference between work and power is that work is is the amount of force you do on an object so it can move at a certain distance. And power is the rate of how much work you put on an object. 

To find work you ONLY need force x distance. 

And to find the power you need work/ change of time.  

For work time doesn't matter BUT in power time DOES MATTER. 😄👌🏼✖️➗

Examples; 

Work done nd lots of power- An example of someone doing work with lots of power is a weight lifter picking up a 50 pound weight above his head with the time of 3s. And the second weightlifter is lifting the same weight but at the time of 10s. Which weightlifter has more power?

Well the second weight lifter because it's takin him more time to lift the same weight at the same distance. 

The one with less time is an expanse of little power because he's not taking all of his power to lift the weight up. 

Inertia investigation

What is inertia? Inertia is the natural tendency of an object to remain still or to keep moving. 

      3 instances I saw inertia in my life are;

A) one example of inertia I've seen is when I'm buying food. When I'm pushing the food cart and I let it go it would naturally want to keep moving. It doesn't want to stop because it has been moving and which is inertia   The cart will not stop unless you hold the cart with your hand and make it stop or there is some object preventing it to keep moving. 

B) second example of inertia is when I'm playing bowling ball. When I roll the bowling ball it would keep going in that direction. The bowling's ball inertia is to keep moving because I'm making it roll. So, in other words the ball will not stop until it reaches the end of the way or it hits the pins. 

C) the third example is when I leave my iPad on the table. This iPad's inertia is to stay still. Why? Well because it wasn't moving it doesn't want to move unless I force  it to move. So this is an example is inertia when staying still. 

      These are the examples of inertia in my life, but one example of when one thing is moving and the other one is not moving is: 

         When people are in the roller coaster the cart is moving every where but the people on it basically doesn't move because they are still sitting enjoying the ride. 😌👌🏼🎢

Mu Friction

Why would friction happen? I think friction happens because everything has to stop at some point. And if it doesn't stop then friction well be the cause of an object stopping. 

   Another surface I think would have an even bigger value of mu with my shoe would be a Rocky Mountain surface. I think this because the rocks would make the shoe less able to slide cuz the surface is rough. 😋👌🏼

Balanced & Unbalanced

This free body diagram shows a balanced object. In other words this object is being pulled and pushes with the same force. How do I know. Well if you see in the diagram both sides  left to right have both with 5n forces. Which means that the object is balanced. 

In this free body diagram the objects are being pulled with different forces. Which means that the object doesn't have a balanced force. So it's unbalanced. This means that the object is being pulled with a string downwards. Because as you can see  the normal force is 600N and the gravational force is 800N which shows that the force isn't balanced because 800 is greater than 600  newtons. 

vector & scalar

                                                             Scalar & Vector


           The difference between scalar and vector is that a vector is a quantity showing the direction and the amount of something. 

Vector - example; the velocity of a car is 3 m/s to the left. This description of the velocity is showing the direction (left) and the amount of something ( velocity). 

            The scalar is also showing the amount of something but without a direction. 
         
         example;  the velocity of the car is 3 m/s. This description of the velocity is showing the amount of something ( velocity).  


           

"Free Body Diagram"

This object is a book and it is moving to the right with acceleration. 

-in this diagram it shows 4 different forces to this object;

  1) Fnorm means normal force which is the force that any object has normally. In this diagram it shows that the book has normal force which is equal to the gravitational force. These are the force that go vertically. 

  2) Fgrav means the gravatational force that the object has from the gravity of earth which is pulling the book down. In this diagram the gravatational force is equal to the normal force. As you can see if you see the vertical forces. 

  3) Ffrict means the force of the friction tht the object when it is being pushed to the right. Which could be the floor or it could be a wall making that force against the book. As you can see in this diagram above it shows that the friction force is small which means that it has friction but it's not a lot. 

  4) The last force shown in this diagram is Fapp which is the applied forced. This force is called this wat because this is the force your are applying to the book so it could move to the ight. As you can see in this diagram the applied force arrow is more than the arrow of the force friction. So this means that the book is unbalanced because the forces horizontally are not equal to each other. 

Four Forces

How many type of forces do you think there are?... Well there are four types of forces we use in our daily lives.😌🆒😱

-The first type of force is called the "Applied Force". This type of force is always some sort of push or pull. Which is caused by a person or thing. 

One example is when you push a cart at shaws. As you are pushing the cart you are applying force to it so it can move from it's place.👌

-The second type of force is called the "Gravitational Force". This type of force is usually a force that is attracting two objects. Usually one of the objects is earth! 

One example of this type of force is when you throw a ball to the ground the gravity doesn't let the ball stay on the ground. So it makes go up again. 

-The third type of force is called the "Normal Force". This type of force is usually a force from a surface. When usually the object is pushing up against gravity. 

One example of this type of force is  holding something on your hand. As you are holding the object on your hand the force of your hand is pushing up the force in the objects force. Which is a normal force because it's usually what happens daily. 

-The last type of force is called the "Tension Force". This type of force is a pulling force. Which is usually in a string,a rope,or chain. 

One example of this type of force is when you are pulling a car with a string. This is a tension force because your adding tension to the object by pulling it with a string. 

Now you know what is a force and the four different type of forces that exist. 😱🆒✅

Distance vs. Time Graphs

                

               How would you detect motion? Well in class we used motion detectors to try to match a graph on the monitor. What we did was that we connected the motion detector to a lap top, second we had someone stand in front of the monitor and they had to walk backwards and towards the detector. As the person was walking the detector was making a graph on the lap top. So when we had the graph we made we then had to match our graph with a graph that the detector already had. After we did the walking we had to record it on a lab we had in our notebooks and explain what movements we had to do so we could make the shape.

                I think these graphs are important in science because with these graphs you can tell if you are moving or not. So it is a good way to detect motion or to show motion. This is a good way to show motion to someone who isn't in the experiment with you.   



Distance v.s Displacement

       Distance and displacement... What do you think these two words mean? Are they the same thing? We'll I'm goin to give you what it means and if they are the same. 😊👌

      What is distance? Distance is the total length traveled from one place to another.  One example in my lab is that the starting point is at zero and ending point is 7 so the distance is 7cm. So distance is the total length traveled. 

       What is displacement? Displacement is the difference of where you started and from where you ended up. There has to be a distance and a direction. An example of this is in my lab which says staring point is 0 and ending point is 5 so the displacement is 5 to the right because the difference between 5 and 0 is 5cm but because it's positive it has to be 5cm to the right. 

      So that is wat distance and displacement are. 📏✏️😊

 

       And sometimes both we'll have the same length and siento es it will be different. 😎

Barbie Bungee Data Estimates🔐

The drop distance for Barbie would be: 

For 10,20,30  rubber bands.

10 rubber bands- the drop distance would be 130 cm

20 rubber bands- 220 cm

30 rubber bands- 400 cm 

I estimated these drops because I know that 8 rubber bands was 118 cm so then I added a little more cm to each more of rubber bands. 😊👌

Metric units

I think we use metric units instead of English units because it's easier to use. For example if were using inches to measure somethin and we wanted to turn it to yards we would hav to do so much math to find how much it is in yards. But if we use metric units it's not that hard because for example if we use kilograms we know that's 100 grams and we wanted to make it to milligrams we know we wuld hav to change it to 1000 grams. 😆👌

3 examples of metric units is: 

A) 2 liter soda bottle 

B) net weight of cereal- 510 grams 

C) 27 grams of sugar in coconut soda 

Estimating Distances

If you had no ruler how would you measure an object. Well I'm going to measure the front of my house. But I don't have a  ruler at all. So how am I going to measure....

Well here is my procedure...

1) in class I measured how many of my foot make 1 meter (4 of them) 

2) I measure the front of my house 

3) if it's 4 feet that means it's 1 meter 

4) if it's a little more of the foot I just estimate to the closest meter 

    Ok my results are 2.12 meters.

The procedure I did was that I walked four steps which I knew was 1 meter, then I walked another four steps and that makes another meter, then when I kept walking to make the last step it took half my foot.( 1 of my foot was 24cm) so I cut the 24 in half and I got 12 so I just add the 2 meters plus 12 and I got 2.12 meters. 

   Reasonable or Unreasonable?

My results (2.12m) is reasonable because I measured it and I was making sure my measurements were accurate. And also it makes sense because it has to be a little bigger than a meter if it's the front of my house so I need to measure from wall to wall. 

Reaction time

 Reaction time is the time someone takes to react to do an action. For example of reaction time is once when I was talking in the phone once in the bathroom and the phone was going to fall in the toilet so I had to react fast to catch the phone so it didn't fall in the toilet. Second, example of my life of reaction time is once the time I had to react when someone was going to throw a ball at me so I could catch it. Another example of reaction time in my life is the time I react to a question someone makes me when I have to answer.