Consider dropping a piece paper and a brick from the same height. Although in theory they should both strike the ground at the same time; in practice the brick will always strike the ground first. The reason is because of air resistance. As the paper falls to the ground air resistance is pushing the paper up, this slows the acceleration of the paper.

It is known that as the velocity of an object increases the air resistance acting on the object increases. If we consider jumping out of a plane and free fall towards the Earth the F.B.D. would be as follows:

Now the force of gravity acting on the object does not change, however as we speed up towards the Earth the force of air resistance is increasing. Eventually there reaches a point when the Fg = Fair when this occurs we are no longer accelerating towards the Earth, but fall with a constant velocity that is called the TERMINAL VELOCITY.

The terminal velocity of an object in free fall depends on two main factors: 1. The mass of the object
2. The surface area exposed to the air resistance

For example: A human free falling towards Earth has a terminal velocity of 190 km/h. If you use a parachute the terminal velocity is about 20 km/h.

If we were to observe this motion on a speed time graph it would be as follows:

Notice that the velocity of the object increase until it reaches a constant value which is the terminal velocity. Also notice that the acceleration of the object is NOT CONSTANT, meaning the constant acceleration equations do not apply, but Newton’s second law still does.

Laboratory:

Design a laboratory to determine the proportionality and proportionality constant between the terminal velocity and the mass. You will have available to you coffee filters, meter stick, tape and a stop watch.

You will submit a Laboratory Report including the following sections:...

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Background Information
Terminalvelocity is when a falling object reaches a constant velocity due to a balance in the forces of weight and air resistance. In this experiment, we dropped marbles of difference weights in 100 ml of oil to calculate their terminalvelocity.
Research Question
How does the mass of an object effect its terminalvelocity?
Aim
Our aim is to measure theterminalvelocity, of marbles of different masses, in oil.
hypothesis
Objects of larger mass will take longer to reach the bottom of the cylinder, whereas objects of lesser mass will take less time to reach the bottom of the cylinder.
Variables
Independent Variable: Volume of oil
Dependent variable: Time taken
Controlled variable: Weight of marbles
Apparatus & Materials
1. Measuring cylinder
2. Oil
3. Weighing machine
4. Marbles of different sizes
5. Timer
6. Paper
7. Pen
8. Calculator
method & procedure
1. Get apparatus ready on a clear table.
2. Get
Data
Calculations
Time taken*length of cylinder = terminalvelocity
Small marble
1st trial – 0.002*18
=0.036
2nd trial – 0.015*18
=0.27
3rd trial – 0.016*18
=0.288
4th trial – 0.035*18
=0.063
Average: 0.657/4
= 0.16425
Medium marble
1st trial – 0.015*18
=0.27
2nd trial – 0.056*18
=1.008...

...less acceleration and once the air resistance is stronger then the terminalvelocity that is when the object is going at a small velocity.
TerminalVelocity
When there is equal force acting on an object when falling such as gravity and air resistance at that stage it is called constant speed or terminalvelocity. When the object is dropped the force of gravity initially is 100% but as it falls the air resistance becomes stronger making the gravity weaker and at one stage there will be terminalvelocity. In some cases due to the mass and weight of an object and the height they fall the terminalvelocity may be quicker or slower.
The Ant and The Man
When the man falls from the 10 story high building and splats to the ground this is because of his fall. When he falls due to the weight of him he falls quicker and gravity has a stronger force on him and air resistance doesn’t and in reality he may not even reach the terminalvelocity or he may reach it near to the ground and hence he is accelerating at a high rate off the building making him splat on the floor.
However when the ant falls from the table which in comparison to the ants height an 100 story building when the ant falls he survives on the floor. This is also linked with the timing of the terminal...

...Velocity and Acceleration (Video Analysis)
NAME
Abstract:
With using the new software this lab was different than the rest. We determined many solutions using video analysis. We used a frictionless track with a “car” and recorded using loggerpro software. We used this software to determine average velocity and instantaneous velocity. With this information we than discovered the average acceleration, mine was .2115. After that we were able to find δa, then finally the free-fall acceleration, I got 1.693. Overall this was a fun and difficult experiment, but I learned a ton about acceleration and velocity.
Introduction:
The average person might hear the word physics and have no idea what it really means. The formal definition is; a science that deals with matter and energy and their interactions. Now that definition is nice and short, and doesn’t explain into too much detail, but that is the gist of it. And hopefully can help you understand this lab a little bit more. The next question an average person is going to ask is when is this even used in real life? But there are many examples, for one; 2-d vectors and projectile are used when using a cannonball, or any other ball flying through the air, every motion on a flat surface. Another example is hitting a golf ball, which can be in kinematics or in dynamics. If only motion of a golf ball is discussed, with terms like...

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Centro de investigación y desarrollo de educación bilingüe (CIDEB)
Physics
LAB REPORT
Uniform Rectilinear Motion
Teacher: Patrick Morris
Alejandra Castillejos Longoria
Group: 205
ID: 1663878
Abstract
The purpose of this experiment, was to prove the concept of the uniform linear motion by using an air track. With this, we demonstrated the impulse and change in momentum, the conservation of energy and the linear motion. We basically learnt to calculate the distance/time, acceleration/time, and velocity/time and graph it. The air track is also used to study collisions, both elastic and inelastic. Since there is very little energy lost through friction it is easy to demonstrate how momentum is conserved before and after a collision. According to the result, the velocity of the object in the air track was constant, it means that it didn’t have acceleration because it has constant velocity.
Introduction
First of all; we should understand what is linear motion. Linear motion is motion along a straight line, and can therefore be described mathematically using only one spatial dimension. Uniform linear motion with constant velocity or zero acceleration. The Air Track can be used to obtain an accurate investigation of the laws of motion. A car or glider travels on a cushion of air provided which reduces friction. Since the friction is...

...Roller Coaster Velocity Report for 8th Grade Science
The performance of our roller coaster, The Gunslinger, was based on the ability to provide an example of Newton’s First Law of Motion, which states; an object in motion stays in motion while an object at rest stays at rest unless acted upon by an unbalanced force. Our design shows that The Gunslinger achieves potential and kinetic energy through gravity and friction caused from the momentum that the acceleration provides.
First we start off with acceleration, which is the increase of speed or velocity. In our roller coaster acceleration happens as you move down the slope, through the loop, and around the curve. Negative acceleration happens as you move up the loop, before the hill and right before the exit path. In order for negative acceleration to happen we need friction. Friction is the rubbing of one object or surface against another. Friction is what makes the object slow down as it moves up the loop and up the hill. Gravity is the natural force or attraction between any two massive bodies. Gravity is what pulls the object down the slope at the beginning of the roller coaster.
Our design of the roller coaster also shows that it is able to accomplish potential and kinetic energy as momentum occurs all through out. Momentum is a measure of the motion of a body equal to the product of its mass and velocity. Therefore, momentum occurs as the object moves down...

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Objective: the purpose of this lab is to investigate the law of conservation of energy. This can be achieved by measuring both potential and kinetic energy through the experiment conducted.
Back ground:
Kinetic energy is said to be the energy of motion. Kinetic energy can be defined through this equation:
KE=12mv2 (equation 1)
Where m is the mass of the object in motion, and v is the velocity of the moving object.
Potential energy is the energy associated with the forces that depend on the position of the object. However, there are specific types of potential energy and in this lab we will consider gravitational potential energy. Gravitational potential energy is the energy possessed by the objected due to earth's gravity. This can be specifically defined by the equation:
PEgrav=mgy (equation 2)
Where m is the mass of the object, g is the acceleration due to gravity and y is the height of the object.
With these energies defined, total energy of the system is the sum of its kinetic energy and potential energy at any point in time.
Total energy= kinetic energy+ potential energy=constant
Therefore the law of conservation of energy is defined as: the total energy is neither increased nor decreased in any process. Energy can be transformed from one to another, and transferred from one object to another, but the total amount remained constant, therefore conserve.
Procedure:
the procedure of this...

...INTERPRETATION OF RESULTS:
This experiment circles around with the Newton’s second condition of equilibrium in rotational motion. It describes by net torque acting on a body which is zero. The ability of the body to rotate in a certain direction is varied according on how much torque is applied. To prove that, a beam that is subjected to two forces is balanced by adjusting the perpendicular distances. When applied force is weight, modification in masses added is also done. Once equilibrium is achieved, or when the beam is not moving at a horizontal position, we can calculate for the unknown forces applied through the utilization of this principle.
We balance the system given the ample forces acting on it. In general, application of Newton’s Second Condition of Equilibrium is applied here. By applying it, we could get the magnitude of one force acting on it, considering the other forces of known magnitudes. Thus, if weight is one of the forces, we could really get the mass of that specific object.
In the first part of the experiment, the first mass pan has 10 g weights on it while for the second, 5 g. By balancing, we measured a distance of 10 cm and 14 cm for each corresponding weight pans, P1 and P2. The weights added to pan 1 and pan2 affect the positions in the model balance if one contained a bigger mass compare to the other. Because they are not equal it will undergo to unstable state and also according to the definition of torque, applied forces multiplied by...

...always be the same distance from the sun. What do you notice about orbits with the shortest years? Why?
Shorter year = closer to the sun. The closer it is to the sun the more of a pull the gravity has on it which causes it to orbit quicker.
8. Choose the ellipses preset from the pull-down menu.
9.You may move the slider bar about 2/3 of the way towards fast for this simulation.
10. Run the simulation until the green planet (body 4) returns to its starting point (one planetary year)
Planet Time of One Orbit (planetary year) Closest Distance to Sun (perihelion) Farthest Distance to Sun (aphelion)
Purple Planet (body 2) 2.2s 54 84
Blue Planet (body 3) 7.6s 54 250
Green Planet (body 4) 14.7s 54 419
11. Change the y velocity of the blue planet (body 3) to 90 and the green planet (body 4) to 70.
12. Run the simulation again until the green planet (body 4) returns to its starting point (one planetary year)
Planet Time of One Orbit (planetary year) Closest Distance to Sun (perihelion) Farthest Distance to Sun (aphelion)
Purple Planet (body 2) 2.4 54 84
Blue Planet (body 3) 12.3 170 250
Green Planet (body 4) 27.0s 294 419
Question Seven:
How does the year of a planet closer to the sun compare with one that is farther away? Why?
The closer it is the shorter the year. The pull on the planet as it gets closer increases thus causing it to orbit quicker.
Question Eight:
How can an orbit be made more circular? Explain...