Unit 4 - Energy
Overview:
Energy is defined as the "ability to do work" or more simply put as the force that causes things to move. There are many types of energy. Some of the more common ones include internal, chemical, elastic and gravitational energy. All these types are divided into two sub groups: Potential and Kinetic energy. Energy can also never be created or destroyed, only transferred. Energy is always conserved so you will always start and end with the same amount of energy.
Energy is defined as the "ability to do work" or more simply put as the force that causes things to move. There are many types of energy. Some of the more common ones include internal, chemical, elastic and gravitational energy. All these types are divided into two sub groups: Potential and Kinetic energy. Energy can also never be created or destroyed, only transferred. Energy is always conserved so you will always start and end with the same amount of energy.
Energy Transfer (LOL Charts):
One way to show Energy transfers is through LOL Charts. LOL charts are bar charts that can express the transfers of energy in a system. They include two bar graphs separated by a circle which indicates the system as well as the energy transfers in and out of the system. |
Energy Problem Solving:
To solve Energy problems, you have to use a combination of Energy Calculations, transfers and modeling. Calculations would include Elastic, Gravitational and Kinetic energy equations. Transfers would relate Work to Force and Models could include F vs Δx graphs as well as LOL charts. |
Work and Power:
Work is when energy is transferred in or out of the system due to an external push or pull on the system. This force could be gravity, friction, or any force that adds adds r subtracts energy from the system. The equation for work is: W-FΔx. Power is defined as the rate of doing work. It can be expressed as joules per second (j/s) or Watts (W). Power=W/Δt. |
Energy, Work, and Power - Forces and Motion:
Energy, Work and power are all heavily related and dependent on Forces and motion. energy can transfer through work which is a cause of a force. Energy is also dependent on motion. Based on the motion of or within a subsystem, Energy and work can change. Forces can also greatly impact Energy, work and power. Forces are basically work that transfer energy. And because power is equal to work over time, power is also effected based on the force exerted.
Energy, Work and power are all heavily related and dependent on Forces and motion. energy can transfer through work which is a cause of a force. Energy is also dependent on motion. Based on the motion of or within a subsystem, Energy and work can change. Forces can also greatly impact Energy, work and power. Forces are basically work that transfer energy. And because power is equal to work over time, power is also effected based on the force exerted.
Representations of Motion, Forces, and Energy:
Motion can be represented on a time vs. x graph. A force graph is force vs. x graph and a Energy graph is represented with a Bar or LOL chart. By looking under the line in all three, you find information about the motion, energy, and forces on the system.
Motion can be represented on a time vs. x graph. A force graph is force vs. x graph and a Energy graph is represented with a Bar or LOL chart. By looking under the line in all three, you find information about the motion, energy, and forces on the system.