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Simple machines are mechanical devices that can be used to increase your force output with mechanical advantage. The 6 different simple machines are pulleys, levers, inclined planes, wedges, screws, and the wheel and axle. There are 3 classes of levers that are differentiated by where the fulcrum is located compared to the load. There is also no unit for mechanical advantage.

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Momentum is mass times velocity. One way to describe momentum is mass in motion. If an object is moving it has momentum. momentum is also a vector so signs will indicate direction. The unit of momentum is the mass unit followed by the velocity unit. For example, if the mass unit is kilograms. and the velocity unit is m/s, then the unit at the end of momentum is kg m/s. Impulse is just the change in momentum. These can be used to calculate collisions between two objects. The two collision types are inelastic and elastic. Inelastic collisions are where the objects collide but do not bounce. Momentum is also conserved in Inelastic collisions. Elastic collisions are where the objects do bounce off each other. Momentum and kinetic energy are conserved in these collisions.

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p=mv
The momentum is found by multiplying mass and velocity.
Δp=FΔt
The change in momentum equals force and the time applied.

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Momentum is seen in many forms. It is used by crash investigators to determine how fast people were going when they crashed among other things.

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Sean hits a .3kg hockey puck with 25N of force and the puck leaves the stick going 30m/s. What is the impulse and how long was the stick in contact with the puck?

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There are two different types of energy, potential and kinetic. Due to the conservation of energy, energy cannot be created or destroyed. Potential energy is the energy stored by the object due to its position. In the equation PE=mgh, the height is the defining position. Kinetic energy is the energy it possess during motion. In the equation KE=(1/2)mv², the velocity is that defining motion. Work is the energy transferred to an object through force over distance. The unit for energy and work is the Joule.

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W=Fd
Work equals force times distance.
PE=mgh
Potential energy equals mass times gravity times height.
KE=(1/2)mv²
Kinetic energy equals one half times mass times velocity squared.
PE+KE=PE+KE
There is never energy lost.

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Work and energy are used today in rollercoasters to calculate how high the humps need to be to get the coaster through the track.

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A 50kg man is whipping around the city in a 2900kg car at 78m/s. Keeping the kinetic energy the same, what is the speed of the car if the driver is 143kg?

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The kinematic equations are the four equations used to find initial and final velocity, acceleration, time, and distance. The acceleration in these equations is constant which means they cannot be used when the acceleration is changing. They also assume all variables are in the same direction. To use the equations you need to use the equation with the missing variable and three known variables.

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Friction is the force resisting motion. It is calculated with the normal force which is mass times gravity times the frictional coefficient which is different depending on the surface. The 3 types of friction are static, rolling, and sliding.

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Mechanical Advantage - force in over force out or length in over length out.
MA= Fo / Fi = Li / Lo
Mechanical Advantage of wheel and axle - radius of wheel over radius of axle.
MAwa = rw /ra
Mechanical Advantage of inclined plane and wedge - length over height.
MAramp = L / h
Mechanical Advantage of screw - two times pi times length over pitch.
MAscrew = 2𝜋L / p
Ideal Mechanical Advantage - distance in over distance out.
MAideal = di / do
Efficiency - work out over work in.
η = W o  / W i

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v=v₀+at
The final velocity equals initial velocity plus acceleration times time.
Δx=(ᵛ⁺ᵛᵒ⁄₂)t
The change in distance equals final velocity plus initial velocity, over two, times time.
Δx=vot+½v2
The change in distance equals the initial velocity times time, plus one half times velocity squared.
v²=v₀ ²+2aΔx
The final velocity squared equals the initial velocity squared, plus 2 times the acceleration times the change in distance.

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F = μN
F is the frictional force, N is the normal force, and μ is the frictional coefficient.

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Friction is everywhere and different materials have different coefficients. You can wear socks and slide on wood floors but without socks you don't. There is also air resistance among other types of friction we see everyday. Brakes also use friction to stop your car every time.

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Kinematic equations are used today to find the basic forces in our everyday life like velocity and acceleration.

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We all use simple machines everyday to move things and use less energy. An example of a lever is a wheelbarrow. An example of a screw is the top of a jar. An example of a wedge is an axe. An example of a pulleys in use is an elevator. An example of an inclined plane is a ramp. An example of a wheel and axle is a car.

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Sean lifts a 53kg object 15m using a pulley. He inputs 13N of force and pulls the rope 200m. What is the mechanical advantage, the ideal mechanical advantage, and the efficiency?

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A plane has a takeoff speed of 90 m/s and requires 1365m to reach that speed. Find the acceleration of the plane and the time required to reach this speed.

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A 3kg rubber block is resting on wet concrete. The coefficient of static friction is .3. What is the minimum force that must be applied to the block to make the block begin to accelerate?