Elastic collision

The moving skate board has more momentum than the stationary train because since the train is not moving its velocity is going to be 0m/s and everything multiplied by 0 is going to be 0, so the train's momentun is 0kgm/s. And the skate board has mass and it also has velocity the skate board is going to have more momentum than the train.

Elastic vs. Inelastic Collision

The difference between Elastic Collision and Inelastic Collision is that when elastic collision happens the two objects will bounce off each other and when inelastic collision happens the objects sill stick together.  An example of inelastic collision is when you roll a marble towards another marble because the marbles are going to keep moving together and at the same speed. And an example of elastic collision is when something small tries to push something big.

Work & Power

   The difference between work and power is that in order to have work you need Force and Distance and in order to have power you need to have work. The power something has depends on the work and the time it takes to do it. If you do a work at .6 seconds and the same work at 20sec. The work done at 6 seconds has more power because it was done faster.a

Mass and Newto's first law

• A bowling ball and a golf ball- A bowling ball has more mass than a golf ball and since it has more mas it has more inertia therefore it will be harder to move so it will need more force than the golf ball.

• A ballom and a rock- The rock has more mass than the ballom because even though the ballom is bigger the rock weights more so the rock has more inertia than the ballom this is why you can move a ballom very easily and it is harder to move a rock.

• If you try to push a car no matter how many times you try you wont do it because it has a lot of mass which means it has more inertia and also because an object that is at rest has to stay at rest unless is acter by another force.

Inertia Investigation

• It is harder to move a big vehicle, like a bus than a smaller vehicle, like a motocycle because tie bigger object has more mass, and the more mas it has the more inertia.

• When a baseball is thrown it will continue to move foward until is acted upon by gravity. Because if an object is moving it will keep moving until its stoped by an unbalanced force.

• Another example of inertia is if you throw a ball off a hill the ball will continue to move until an object or anither force stops it.

Mu- Friction

Friction is a force that acts on an opisite direcrion to movement. Friction happens because without it we couldn't be able to do anything. Something that will have a bigger value of mu with your shoes will be a floor that is smoth because it is easier to walk and it will make more friction.

Free body diagram

    The object I chose was a person I  couldn't put the picture. The car has a net force of 0n because it has a balanced force. This means that if The person has a gravitational force of 20n the normal force will be 20n because the same force that is pulling it to the center of the earth is also pushing it off the ground.


   An object that has an Unbalanced force is an egg falling off a tree. This object is unbalanced because there is no force that is pushing it up so there is not an normal force the only force that it has is gravitational force because its going doen to the center of the earth until something stops it.

Balanced and Unbalanced

A free body diagram that is balanced is a car because the same amount of force that is pulling it to the center of the earth is also pulling it off the ground. A free body diagram that is unbalanced is when it has different pulls. For example if there's an object and the Fg is 6n and the Fn is 4n its going to be unbalanced because the force that is pulling the object to the center of the earth is greater that the force that is pulling the object off the groung

Vector & Scalar

       The difference between vectors and scalars is that a Verctor is a number showing magnitude and direction and its used in: velocity, acceleration, force, weight and displacement, for example if you drive 7 meter to the right and then go 3 meters to the left and the answer will be 4 meters right. And a Scalar is an amount with olny magnitude and its used in: distance, speed, time and mass, for example if you go 7 meters to the right and then 3 meters to the left the scalar will be 4 meters..

Four Forces

  

                                           Four forces


    Applied Force- Means to push or pull on a system. For example when I push a toy Im doing Applied force because Im pulling something. 

   Gravitational Force-  Is a force that is attracting two objects. For example if I drop a basketball on the floor the gravitational force is going to make it touch the floor, if there was no gravitational force instead of falling on the floor the basketball will be floating.

   
    Normal Force- Means a force of a surface, it's like pushing against gravity. For example if I put my notebook on my hand it's going to stay there because I'm preventing the notebook from falling.

    Tension Force- It's like a pulling force. For example if I bungee jump that will be tension force because the string will pull me back up and ir will prevent me from hitting the floor.

Guess Method

                                             Guess Method

• G = The units that are given

• U =  The unit that is unknown

• E =  An equation made to find out the unknown number

• S = When you substitute the equation by the given units

• S = To solve the equation to find the unknown number

For example: 

    Martín drives a total of 200meters in 25seconds. What is the average speed of Martín driving during this interval?

G =                                        E =

d= 200meters                         S = d/time

Time= 25 seconds

U =                                         S =

Speed= ?                                   S = 200m/25seconds

                                               

                                               S =

                                                   S= 200m/25sec. =  8meters/seconds

Distance vs. Time Graphs

      Today we learned about motion and we got to use a motion detector it was really fun and we had to match a graph that was on the computer it was a little hard because sometimes you had to go fast backwards or frontwards and we had to make sure that we were doing it at the right speed, I think my group did it pretty well because we were really close to the graph that was given on the computer.


       I think that we will need this in science because we might have to try to match some graphs and datas that the teacher gives us or something like that...
 

Distance vs. Displacement

Displacement means the difference between a starting and a ending position
Ex. If you walk 10 miles right and then you walk 3 miles left your Displacement will be 7 miles right because the distance between your starting and andino position is 7 mires right.

Distance means the total length traveled
Ex. If you walk 10 miles right and the 3 miles left your distance will be 13 miles because it's the total how how much you walked.

Barbie Bungee Data Estimate

      I think that the drop distance would be for Barbie if it had 10 rubber bands will be about 155cm because 8 rubber bands was 135 and 10 has to be close to that number. The drop distance of Barbie if it had 20 rubber bands  is about 300cm because if 10 rubber bands is 155cm then it will have to be double and because it's not going to be linear I think it will be about 300cm. The drop distance of barbie if it had 30 rubber bands is 445cm because if 20 rubber bands is 300cm then 40 rubber bands will be 600cm and 600-155 which is 10 rubber bands is 445cm.


10 rubber bands= 155cm
20 rubber bands= 300cm
30 rubber bands= 445cm

Metric Units

   We use Metric System in science because it's more simple than English System and it's also more convenient to work with base 10. We use metric units in a tape measure calibrated in (cm), in a Degress Celcius, and also in a kilogram weight.

Somethings in my house that have metric units are:

• Salt because it's weighted in grams

• My window is about one meter and a half

• The furniture at my house can measure about 3 meters and a half

Estimating Distances

Procedures of how I estimated the length of the front of my house:

• I figured out how many feet did I need to make a meter
• I counted how many feet was it to walk across my house
• I changed feets to meters, and I got my answer

My house is about 9.75 meter long this is reasonable because my house is not that big and I double checked after I got my answer

Reaction time

Reaction time is the time that it takes to react to a situation, Reaction Time has happened to me many times some of them are:

• When I went for a walk with my baby cousing and his carriage went down a hill because I got distracted.

• When I has to catch a jar that was going to fall

• When I was crossing the street and a car almost crashed me.