Unit 8: Work and energy

Unit 8 is about work and energy. Work is any change in energy. Work is a scalar quantity, which has magnitude or muchness. The units of work are Newton-meters also known as a joule. (J) Work can also be defined as working against a force. Work is equal to force times delta distance. (W=F∆d)

We also learned about energy. The law of conservation of energy states that energy cannot be created or destroyed. It can only change forms. Energy in is equal to the energy out just like momentum. The energy an object has due to its position in a gravitational field is a product of mgh. Mgh is mass, acceleration due to gravity and h stands for position. Kinetic energy is the energy of motion. (KE=1/2mv^2)

Power is the rate at which work is done. Power is equal to work per time. (work/time=joules/second=watt) Joules per second is also known as a watt.

The elastic limit is the most the string can stretch before deforming. 

For graphing for a force versus distance graph, the slope is spring constant. Spring constant is N/m. The area under the curve of a force versus distance graph is work done.

We also learned today that potential is a bad word because if someone says you have potential it means that you're good, but not actually. Instead of having potential, we should want to attain it.

This shows work because while we are all holding our slippers, we're all walking or moving. If you're not moving but carrying your slippers, that does not mean that you are doing work.