Work, Energy, and Power Flashcards
What is Energy?
The property that must be transferred to an object in order to perform work on, or to heat, an object.
What is the difference between kinetic and potential energy?
Potential energy is the energy of an object or a system due to the position of the body or the arrangement of particles of the system, whereas Kinetic energy is the energy of motion.
How do potential and kinetic energy relate to work?
Kinetic energy is created when potential energy is released, spurred into motion by gravity or elastic forces, among other catalysts; when work is done on an object and it accelerates, it increases the kinetic energy of an object.
What is the difference between conservative and non-conservative forces?
Non-conservative forces are determined by the path taken, whereas conservative forces are not determined by the path taken.
What are some examples of conservative forces?
Some examples of conservative forces include gravitational force, spring force, magnetic force, FA, FN, & Fg.
What are some examples of non-conservative forces?
Some examples of nonconservative forces include friction, air resistance, and tension in a cord
What is work?
A force acting over some amount of distance to cause a change in energy. Work is done when there is a displacement of the point of application in the direction of the force. Work can also be defined as the process by which a force transfers energy into or out of a system.
List a situation in which no work is done on an object.
No work is done when an object is held but not moved, since there is no displacement.
List a situation in which negative work is done on and object.
Negative work is done by the gravitational force when a person climbs a tree.
List a situation in which positive work is done on an object.
Positive work is done when a door is pushed open, seeing as how the force and the motion are in the same direction.
What type of system is a pot boiling with the lid on? Explain.
This is an example of a closed system, due to the fact that energy is not conserved but matter is.
What type of system is a thermos with ice cold water in it? Explain.
This is an example of an isolated system, due to the fact that energy and matter do not change and there is not an allowance of an energy transfer.
What type of system are plants? Explain.
This is an example of an open system due to the fact that energy is conserved and neither is matter and there is a constant transfer of energy.
What is Power?
Power is the amount of work done or change in energy done in a certain amount of time. Power is the rate of doing work, the amount of energy transferred per unit time.
How is power calculated? (formulas)
P = W/t(s), P = Force x velocity, P = delta e / time
What is an open system?
An open system is a system in which matter and energy are not conserved.
What is an isolated system?
An isolated system is a system in which matter and energy are conserved.
What is a closed system?
A closed system is a system in which matter is conserved, but energy is not conserved.
What is the work energy theorem? (equation & definition)
The work-energy theorem states that the network done by the forces on an object equals the change in its kinetic energy. W = deltaKE = 1/2mv^2f - 1/2mv^2i
What are the formulas for work?
W = F(d)cos (theta), W = Fd
What is Mechanical energy?
Mechanical energy is the sum of the kinetic energy as well as the potential energy.
What has to be true about the Mechanical, Potential, and Kinetic energy within an isolated system?
Within an isolated system nothing, not even energy, can enter or leave. Whatever you started with you finish with. The mechanical energy is the sum of the potential in kinetic energy throughout the entirety of the system and when one energy decreases, the other one in turn, will increase.
What is the Law of Conservation of Energy?
The law of conservation of energy states that energy is not being created or changed, it is only changing forms or transferring from one object to another.
How are work, energy, and power related?
A force is said to do work if, when acting, there is a displacement of the point of application in the direction of the force. Is the property that must be transferred to an object in order to perform work on, or to heat, the object. Is the rate of doing work, the amount of energy transferred per unit time.
