Lecture 31 - Work Energy Theorem Flashcards
what is required to transfer energy
work is required to transfer energy
what happens when a golf club hits a ball
ball goes D shaped, compressing it and then expands off the slub which is where the energy is transferred into the ball
explain the transfer of energy in a golf club swing
golfer does work on the club, energy transferred from golfer to the club
the club does work on the ball, energy is transferred from club to the ball
energy in the ball
the amount of work we do tells us
how much energy we will transfer from one object to another
what is the work - energy theorem
the energy associated with the work done by the net force does not disappear after the net force is removed (or becomes zero), it is transformed into Kinetic Energy of the body
W = E2 - E1
the net work done by all the force acting on a body equals
the change in its kinetic energy
work changes the what of a system (the equation also)
the energy of a system
W = 1/2m vf^2 - 1/2m vi^2
will there be any work done when someone falls but they havent touched the ground yet
no because gravity is the only force acting and this is a conservative force which means energy is conserved and no work is done
is there any work done if someone falls and touches the ground
yes because there is a change in height and velocity, the external ground force acts on the body, meaning the total mechanical energy of the system has changed and work has been done
what is the coefficient of restitution
helps quantify how much kinetic energy is lost due to work done by non conservative forces
in a real work collision, some of the initial kinetic energy is…
is converted into other forms of energy, leading to a reduction in the final kinetic energy
what is transfer of energy
the mechanism by which energy is passed from one body to another
why can an object continue to move even after we have stop applying force on it
because the work we do changes the energy of the system, so the object has energy
the energy associated with the work done by the net force does not ….
disappear after the net force is removed, it is transformed into the kinetic energy of the body
- we call this the work energy theorem
the net work done by all forces acting on a body equals
the change in its kinetic energy
