"What I learned in 1st Semester"

This semester I learned a lot!! The first unit we learned about was Kinematics (1-dimensional and 2-dimensional).  I learned that kinematics is the study of motion.  This is the basics of physics.  After we learned about kinematics, we learned a little bit of graphing that goes deals with kinematics.  The next unit was Forces and Motions. In this unit I learned Newton's 1st, 2nd, and 3rd laws of motion.  I learned that a newton is in units of kg m/s^2 and that weight = mg. Also in this unit we learned about pulleys and because it has one string, that means there is one tension.  Momentum was the next unit we learned about.  I learned taht momentum is a vector that is calculated by multiplying mass times its velocity (units: kg m/s). The law of conservation of momentum is that momentum cannot be created nor destroyed, it can only change forms, so therefore, momentum in equals momentum out.  Similar to this law of conservation, I learned about the law of conservation of energy which basically stated that energy in equals energy out, in the our unit of Work and Energy.  I learned much information this semester and many equations.  All this information and knowledge I learned was written down in my physics notebook so that I will never forget. :)

DO WORK SON!

This week we learned about work and energy.  Work is activity involving effort to achieve a result.  To find work you can multiply the force on the object by its displacement.  The units of energy used is Nm, also known as Joules.  Work = the change in energy.  According the the law of energy, energry cannot be created nor destroyed; it can only change forms (in an isolated system).  The energry of position is an object's potential energy.  You can calculate an object's gravitational potential by multiplying its mass by the gravity by its height.  After learning about work and energy, it reminded me of this weekend.  My mom and I were sitting at the table and she asked me to pass her my pencil case.  I was too lazy to pick it up and hand it to her, so I slid it across the table.  I pushed my pencil case about 1/2 a meter.  If it took a force of 3 N to push the pencil case, the work I would being doing would be 1.5 Joules.  I'm glad I got to learn about Work and Energy this past week, so now I know how to what work and energy is and how it is applied.