Work Energy Principle Examples

The principle of work and kinetic energy also known as the work energy theorem states that the work done by the sum of all forces acting on a particle equals the change in the kinetic energy of the particle.

Work energy principle examples.

If the net work done is positive the kinetic energy is going to increase and the object s going to speed up. For example a 2 kg mass moving with a speed of 3 m s has a kinetic energy of 9 j. The work energy theorem is useful however for solving problems in which the net work is done on a particle by external forces is easily computed and in which we are interested in finding the particles speed at certain positions of even more significance is the work energy theorem as a starting point for a broad generalization of the concept. Note that the work in this equation is the work done by the net force rather than the work done by an individual force.

Here k e f is the final kinetic energy and k e i is the initial. Conversely a decrease in kinetic energy is caused by an equal amount of negative work done by the resultant force. The above derivation shows that the net work is equal to the change in kinetic energy. This relationship is called the work energy theorem.

1 2 mv 2 kinetic energy is a scalar quantity with the same units as work joules j. If the net work done on an object is negative the kinetic energy of. This definition can be extended to rigid bodies by defining the work of the torque and rotational kinetic energy. Work transfers energy from one place to another or one form to another.

The change in the kinetic energy of an object is equal to the net work done on the object. There is a strong connection between work and energy in a sense that when there is a net force doing work on an object the object s kinetic energy will change by an amount equal to the work done. This information is referred to as the work energy principle and is derivable from the law conservation of energy. The change in kinetic energy of a body is equivalent to the net work done on the body.

In more general systems work can change the potential energy of a mechanical device the thermal energy in a thermal system or the electrical energy in an electrical device. Principle of work and energy. This section focuses on the work energy principle as it applies to particle dynamics. The work energy principle says states that.

The work energy principle states that an increase in the kinetic energy of a rigid body is caused by an equal amount of positive work done on the body by the resultant force acting on that body.