The formulas are:
Work = Force * Distance (where force and distance must be parallel and must be proportional)
Power = work/time
Work In = Work Out
Fin * Din = Fout * Dout
If we were to have a 30N box, and had to travel a distance of 2m in 3 seconds, how much power do I need? How much work is done?
In order to solve this, you must solve for work first so, you use Work = Force * Distance
Work = F * D
Work = 30N * 2m
Work = 60J (work is measured in joules)
Now I can solve for power using, Power = work/time
Power = work/time
Power = 60J/3s
Power = 20W (power is measured in watts)
Work also equals the change in Kinetic Energy.
Kinetic Energy is the energy of movement and written as KE.
The Formula for KE is:
KE = 1/2 m v
²∆KE = KE final - KE initial (this is another way to solve for work)
Then there is potential energy. Potential energy is the lowest point in which an object can be located. Potential Energy (PE) and Kinetic Energy (KE) are inversely related to one another.
Machines are used in order to make the force in work easier. These machines range from inclined planes to pulleys. An example of how inclined planes help decrease the force in the object is shown below.
If I were to have a 50N box and needed to lift it 1m its force would be to much for me to be able to lift, so I would use a ramp that is 10m long which is the new distance and knowing work in = work out I would only need to use 5N of force. Machines are used to make your life much easier.
I didn't really struggle this semester, I didn't do well on a major quiz however, but that was due to me being lazy and not checking back over my work. I am feeling pretty confident about this test however. I also managed to meet my goal for this unit which was turn in all of my homework, and I plan to make that my goal for the next unit as well as getting at least a B on the test. Now here is a video my group made about machines.
