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The Kinematic equations is not one topic, but rather equations that will guide you throughout all of physics. They are like baseline equations, and when you are given hardly anything you can always start with these to get going. The kinematic equations deal with travel both vertically and horizontally. The components that make up the equations are, Distance, Time, Velocity, and Acceleration. There are four basic equations shown further below. The reason these equations prove so useful throughout all physics is that if the given problem is missing an element such as time you would still be able to solve it by using the equation that doesn't require time. Now as I said the basic elements of these equations involve distance, how far something is, time, how long something takes, velocity, how fast something is moving, and acceleration, the change of an objects speed. The standard units for each is as follows- Distance (M, Meters), Acceleration(M/Sˆ, Meters per second squared), Time(S, Seconds), and Velocity(M/S, Meters per second)

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A baseball is throw straight upward and returns to the point from which it was thrown after 5.0s. What was the baseballs original speed? What was the maximum height the ball reached?

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First the most important thing to know is that the total time is 5 seconds which means it took 2.5s to reach the peak. The second thing to know is that at the peak the velocity will be zero because it is not going up anymore. Finally the acceleration is equal to -9.8m/sˆ2 because you are throwing up against gravity thus it will be negative. From there you can plug in all your new found givens and solve for both Velocity and Max height.

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Force is an action usually represented by either a push or pull Force is defined by its strength, direction, and units. The SI unit for force is one Newton(N). One example of force is gravity. An objects force(weight) can easily be calculated by simply multiplying an objects mass times the gravity of the planet. For earth that would be 9.8N. Force directly applies to Newton's first three laws. The first states that an object in motion will remain in motion unless acted upon by an outside force. This is easy enough to comprehend, if you roll a ball it will keep rolling until something stops it like a wall. Here comes in the concept of friction. Friction is like the universal force acting against moving objects. Newtons first law also adds that an object at rest will stay at rest until another force acts upon it. Once again easy to understand as a ball will not begin to roll unless someone throws it. Now the second law is perhaps the most well known physics equation - F=ma or Force equals mass times acceleration. The force applied to a moving object will be can be found by seeing how fast the object increased speed multiplied by its mass. Newtons final law applies to when two objects interact with each other. This law is that every action will have an equal an opposite reaction which simply means that forces come in pairs. For every rolling ball there is a person who initially rolled it. Now onto springs. Springs are other objects that exert force when they are released. The equation to calculate the force of a spring is found in Hooke's law. Everyday we use force from opening a door to chewing our food, and by force we do everything.

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One important part of testing a car is seeing how fast it can brake. A 1,100 kg car is traveling at 15 m/s when the brakes are suddenly applied. How far a distance will it travel if the brakes can exert a force of 6,000 N?

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Force is equal to mass times acceleration so if we are given mass and force we can find acceleration. Because the car is slowing down the acceleration is in the negative direction. From there you can plug your acceleration into the kinematic equations to find how far you car would travel before it came to a complete stop. Finally Newtons third law. Without this no action could occur. Without a first force no other force could occur. I like this especially because it reminds me a created universe needs a creator. If objects didn't need an original mover then everything would move about freely and chaotically. Forces keep the world put and intact.

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Forces are all around us and besides energy this might be the second most used physics concept in daily life. Force can be anything from opening a door to writing on a piece of paper. Now how they apply to the world is crucial. Without force nothing would be able to operate and everything would be chaos. Think of newtons first law if objects continued to move freely even after coming in contact with other forces cars wouldn't brake or baseballs would travel on forever. Forces keep us grounded, especially gravity. Newtons second law can be seen a lot in construction or moving. If you need to get a large object moving a certain speed you can calculate the need force to get the object to this speed.

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Fw= mg - Force weight of an object is equal to its mass times gravity. This is used for all objects and you will typically use the earths gravity of 9.8 m/sˆ2
F1+F2+F3...=0 - At equilibrium all the forces will add up to be equal to zero
a=F/m - acceleration of an object is equal to its force divided by its mass. The more common expression for this equation is that force is equal to mass times acceleration
F=-kx - the force of a spring is equal to the spring constant times the distance the spring either compressed or stretched.
Ff=μ(s)Fn - force of friction is equal to the static friction coefficient times the force
Ff=μ(k)Fn - force of friction is equal to the kinetic friction coefficient time the force
Ff=μ(r)Fn - force of friction is equal to the rolling friction coefficient time the force

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The most common example of these equations in the world today is in driving. We use movement every time we walk and run, but the easiest way to see these in action is when driving. While it is pretty hard to calculate the time it takes you to get from light to light based on the distance and velocity while driving, but a lot of GPS servicing works through these equations. It uses the distance, the speed limit, and other factors to calculate how long it will take you to drive from point a to B. Once again you are very unlikely to ever use these equations outside of a physics standpoint, but it is interesting to understand how GPS systems work, and also how simple it is to calculate your movement. Finally these equations show that in physics all you need is a few variables. There are so many equations, and theories that you can solve practically any problem even if just given a few variables to start with.

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V=Vo+at - Velocity final is equal to velocity initial plus acceleration times time. This is used when you don't have a distance.
∆x= 1/2(V+Vo)t - Change in distance is equal to velocity initial plus velocity final divided by 2 all multiplied by time. This is used when you are not given acceleration
∆x=Vot+(1/2)atˆ2 - Change in distance is equal to velocity initial times time plus one-half times acceleration times time squared. This is used when you do not have your final velocity.
Vˆ2=Voˆ2+2a(∆x) - Final velocity squared is equal to velocity initial squared plus 2 times acceleration time the change in distance. This is used when you are not given time

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Everything in the universe operates through energy, and work is a from of energy. Energy can appear in two forms kinetic and potential. The great thing about energy is that it can neither be created or destroyed. Some experiences of energy we see everyday include light, heat, and electricity. There are many types of energy from mechanical to nuclear. Energy is seen through work which is the force applied multiplied by the distance moved. Work is measured in Jules(J). Now for potential and kinetic energy. Potential energy is energy that is still. It is the maximum amount of energy an object can exert at its certain height, mass, and gravitational pull. For instance if you were at the peak of a rollercoaster not moving you would have all potential energy. Now kinetic energy is the energy of motion. This is when you are heading down the rollercoaster. This can be calculated from the velocity and the mass of the object. Now at times you can have some potential energy and some kinetic. There will be total kinetic energy when the height is zero and there will be total potential energy will be when the velocity is zero. Since energy can be neither destroyed nor created your maximum potential energy will be equal to your maximum potential energy. So the potential energy you have at the peak of the rollercoaster will be equal to you kinetic energy at the bottom. Along with measuring the energy you can also measure the flow of energy. The rate at which work is done, or the rate at which energy is transferred, is called power. Power can be calculated from the change of energy over the change of time. Power can also apply to electrical energy like that which flows through a battery. This is found by multiplying the electrical current by the voltage). The units for these are as follows- power(W, Watts), Electrical current(A, Amps), and Voltage(V, Volts). Energy is all around us and everything we doo from walking to typing physics projects uses energy.

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How far is a spring extended if it has 1.0 J of potential energy and its spring constant is 1,000 N/m?

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The most important thing to know here is that because of the conservation of energy potential energy is going to be equal to spring equal. This allows us to substitute the 1.0 into the spring energy equation then solve for x.

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Energy is hands down the most used physics concept in the world. Everything we do requires energy form waking up in the morning to washing the dishes. Energy keeps the world moving, and without it everything would stall out and shut down. Now many different types of energies go into making the world function. Factories use electric energy to produce products, Nuclear plants produce energy, and humans use energy in all they do. The most crucial is the human energy, because if humans don't have energy all else fails. That is why our bodies require us to sleep, eat, and drink so we can replenish the energy we used through the day. When we are born it is like having all the potential energy, and slowly we use it and we replenish it over time, but never fully, and eventually we run out and die. Apart from humans energy is used to calculate anything from how to make a functioning rollercoaster, to how fast you can speed down your hill on a bike. Energy is the basic function of life and without everything would cease to move.

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W=FxD - Work is equal to Force times Distance.
Ep= mgh - Potential Energy is equal to mass time gravity time height
Ek= 1/2mvˆ2 - Kinetic Energy is equal to one-half times mass times velocity squared
Ep(Spring)=1/2kxˆ2 - potential energy of a spring is equal to one-half times spring potential(K) times the stretch or compression of the spring (X)
P=∆E/∆t - power(watts) is equal to the change in energy over the change in time
P=IV - Power(watts) is equal to electrical current multiplied by the voltage

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A simple machine is a mechanical system through which an applied input force directly creates an output force through a single motion. A simple machine has no source of energy except the instantaneous work done by the input force. The six simple machines are as follows: Lever, Pulley, Wheel and Axel, Wedge, Inclined plane, and Screw. These machines make tasks that require a lot of force require less force through a simple machines mechanical advantage. mechanical advantage is simply how well the simple machine works. The easier a task is to complete usually the mechanical advantage will be larger. Now these Machines also have what is know as mechanical efficiency. This is how efficient the machine works. For example if if you applied 10N of force and the mechanical advantage was 10 you would expect 100N of output force. However simple machines will never work 100% so if you were to put in 10 N of force and the output was 90N of force the simple machines would have an efficiency of 90%. Each simple machine requires a different equation to calculate its mechanical advantage, but narrowed down the entire chapter can be summarized as force output over force input.

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Larissa and Kasey built a black-and -tackle assembly to lift a 15kg box. They had to pull their end of the rope with an input force of 120N. Furthermore, they moved their end a distance of 3.0m to lift the box 150cm. What was the efficiency of the block-and-tackle assembly?

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Since we are solving for efficiency we need to convert our units into work. To do this we must multiply our forces by the distance exerted. Also be careful as on was in CM that had to be converted to M. Once you find both work exerted and work inputed you can divided the two and find your efficiency percentage.

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Simple machines are used all around use to make life move more smoothly. They are used in cars, household appliance, but where they are most common is in construction. Construction require=s moving and holding in place lots of heavy materials, and simple machines allow for moving these materials without needing thousands of people to lift them. Cranes for instance use pulleys to lift large beams into place, and you will also see many pulleys throughout a construction site carrying random materials like bricks. Now other simple machines are implemented to keep these large materials in place. Large beams are placed at an incline to hold walls intact, and screws are used to connect two pieces of material. Simple machines allow for production and life in general to move more quickly because without them we wouldn't be able to build skyscrapers, or even screw in a light bulb.

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MA=Fo/Fi -Mechanical Advantage is equal to force output over force input
MA(lever)=Li/Lo - Mechanical Advantage of a lever is equal to the length input of a lever of the length output of a lever
η=Wo/Wi - Efficiency is equal to Work output over work input. Two things to not 1. this answer will be a precent 2. Work is not force, force is mass times gravity, work is equal to force times distance.
MA(ideal)=Di/Do - Mechanical adnatage ideal is eqaul to the distance output over the distance input
MA(wheel and axel)=Rw/Ra - Mechanical Advantage of a wheel and axel is equal to the radius of the wheel over the radius of the axel.
MA(gear)=To/Ti=Output teeth/input teeth - Mechanical Advantage of a gear is equal to its torque output or the number of output teeth over the torque input or the number of input teeth.
MA(ramp)=Lramp/Hramp - Mechanical Advantage of a ramp is equal to the length of the ramp over the height of the ramp
MA(wedge)=L/H - Mechanical Advantage of a wedge is equal to the Length of the wedge divided by the wedge height
MA(screw)=2πL/p - Mechanical Advantage of a screw is equal to 2 times pie time the length of the screw over p ( p is the distance in between the grooves of a screw).

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Momentum is very simple put the mass of an object times its velocity. Momentum's unit is in kg m/s because it is the mass(Kg) times the velocity (M/S) Thus the larger or faster an object is moving the greater momentum it will have. Momentum is also a vector as it has a direction involved so when calculating for momentum it can either be positive or negative. Now impulse is much like momentum only slightly different. Impulse occurs when an object strikes another object and has an opposite momentum after collision. Much like if a ball traveling 40m/s struck the ground then bounced back at 20m/s. Impulse is calculated by subtracting the final momentum from the initial momentum. Another way to describe momentum is the force applied times the passage of time. Now with momentum and impulse comes the conservation of momentum. This states that much like energy momentum will always remain equal so if a car had a momentum of 50 kg m/s and it struck a stationary car, if one car moved away at - 5kg m/s then the other car would move at 50 kg m/s. Simply put when a collision occurs the momentum will remain the same as a total it may just be in different quantities and directions. Finally comes collisions. There are three different types of collision, Perfectly inelastic, inelastic, and elastic. the easiest is Perfectly inelastic as when the collision occurs the two objects stick together. Now with an inelastic collision the two objects will not react with the same momentum. For example if two cars hit and one travelled at 5kg m/s and one at -10 kg m/s. Finally is elastic collision and this is when eh tow objects collide and maintain the same momentum as if tow cars his and each then had a momentum of 10 kg m/s.

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A motionless 200kg astronaut is holding a 7kg tool while on a space walk. To get moving the astronaut throws the tool forward at a speed of +4.1m/s. How fast does the astronaut move backward?

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This problem employs both momentum and conservation of momentum. Which means our initial velocity times mass will be equal to the final mass time velocity. Because our initial velocity is zero we can plug in our remaining variables then solve for the velocity of the astronaut.

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Momentum and impulse is a physics concept you don't see as often in the world compared to energy or force, but it is still very relevant. Where I see it most is in sports and in Car Crashes. In Car crashes it is obvious how momentum and collisions apply, but the cool part is that investigators can use the skid and distance the cars traveled after initial impact to determine from where and how fast the cars were going when they struck each other. Because momentum will carry over through collision investigators can take the mass of the cars and the total distance traveled to calculate the speeds of the cars to determine wether or not the collision was due to high speeds. Momentum and impulse can be seen in many sports, but especially in golf, baseball, and basketball. In basketball you dribble the ball against the floor and the harder you pound the ball the greater the impulse from the floor will be causing the ball to launch high into the air. In baseball the pitcher throws the ball with initial momentum and once the bat strikes the ball it's impulse occurs causing the ball to fly far away. Much like baseball, a golfer uses momentum to carry the club through their swing then applying an impulse to the ball causing it to soar down the course. Momentum is a very important concept to professional athletes and investigators as they try to master their craft.

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P=mv - Momentum is equal to mass time velocity
J=∆p=F∆t - Impulse is equal to change in momentum is equal to force divided by the change in time

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Explanation      6/6
Problem            3/3
Video                 4/4
Real World        5/5
Equations         2/2

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Explanation      6/6
Problem            3/3
Video                 4/4
Real World        5/5
Equations         2/2

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Explanation      6/6
Problem            3/3
Video                 4/4
Real World        5/5
Equations         2/2 (great explanation of the equations)

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Explanation      5/6 (a few grammatical errors)
Problem            3/3
Video                 4/4
Real World        5/5 (absolutely good example)
Equations         2/2 (good explanations)

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Explanation      6/6
Problem            3/3
Video                 4/4
Real World        5/5
Equations         2/2