Define nonconservative forces and explain how they affect mechanical energy.
Show how the principle of conservation of energy can be applied by treating the conservative forces in terms of their potential energies and any nonconservative forces in terms of the work they do.
The information presented in this section supports the following AP® learning objectives and science practices:
4.C.1.2 The student is able to predict changes in the total energy of a system due to changes in position and speed of objects or frictional interactions within the system.
(S.P. 6.4)
4.C.2.1 The student is able to make predictions about the changes in the mechanical energy of a system when a component of an external force acts parallel or antiparallel to the direction of the displacement of the center of mass.
(S.P. 6.4)
Nonconservative forces and friction
Forces are either conservative or nonconservative. Conservative forces were discussed in
Conservative Forces and Potential Energy . A
nonconservative force is one for which work depends on the path taken. Friction is a good example of a nonconservative force. As illustrated in
[link] , work done against friction depends on the length of the path between the starting and ending points. Because of this dependence on path, there is no potential energy associated with nonconservative forces. An important characteristic is that the work done by a nonconservative force
adds or removes mechanical energy from a system .
Friction , for example, creates
thermal energy that dissipates, removing energy from the system. Furthermore, even if the thermal energy is retained or captured, it cannot be fully converted back to work, so it is lost or not recoverable in that sense as well.
How nonconservative forces affect mechanical energy
Mechanical energy
may not be conserved when nonconservative forces act. For example, when a car is brought to a stop by friction on level ground, it loses kinetic energy, which is dissipated as thermal energy, reducing its mechanical energy.
[link] compares the effects of conservative and nonconservative forces. We often choose to understand simpler systems such as that described in
[link] (a) first before studying more complicated systems as in
[link] (b).
Questions & Answers
Ayele, K., 2003. Introductory Economics, 3rd ed., Addis Ababa.
what's the difference between a firm and an industry
Abdul
firm is the unit which transform inputs to output where as industry contain combination of firms with similar production 😅😅
Abdulraufu
Suppose the demand function that a firm faces shifted from
Qd 120 3P
to
Qd 90 3P
and the supply function has shifted from
QS
20 2P
to
QS
10 2P .
a) Find the effect of this change on price and quantity.
b) Which of the changes in demand and supply is higher?
Demand curve shows that how supply and others conditions affect on demand of a particular thing and what percent demand increase whith increase of supply of goods
Israr
Hi Sir please how do u calculate Cross elastic demand and income elastic demand?
Abari
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