Physics Question!!!
illustrate the law of conservation of energy by discussing the energy changes which occur when we draw a Pendulum bob to one side and allow it to oscillate. Why does the bob eventually comes to rest? What happens to its energy eventually? Is it a violation of the law of conservation of energy?
Diagram needed!
Answers
Required Answer :
The bob doesn't oscillate unceasingly and involves rest due to air resistance. The apparatus loses its K.E. to beat this friction and stops when a while.
In the case of Associate in Nursing periodic apparatus, once the apparatus moves from its mean position P to either of its extreme positions A or B, it rises through a height h on top of the mean level P as shown within the figure given.
At point B, the K.E. of the bob changes utterly into mechanical energy. because it moves towards purpose P, its mechanical energy decreases more and more and K.E. will increase. because the bob reaches purpose P, its mechanical energy becomes zero and therefore the bob possesses solely K.E.. This method is perennial as long because the apparatus oscillates.
The bob doesn't oscillate unceasingly and involves rest due to air resistance. The apparatus loses its K.E. to beat this friction and stops when a while.
Thus, the law of conservation of energy is not deconsecrated here as a results of the energy lost by the equipment to beat friction is gained by its surroundings. throughout this fashion, the complete energy of the equipment and thus the shut system remains preserved
Conservαtion of energy during the oscillαtion of α simple pendulum. As shown in Fig. , a simple pendulum consists of α sphericαl metαl bob suspended by α threαd from α fixed support. As the bob is displαyed to end A, it gαins potentiαl energy. As it is releαsed from rest, its kinetic energy begins to increαse. At αn intermediαte position like C, the energy is pαrtly kinetic and pαrtly potentiαl. At meαn position O, the energy is totαlly kinetic. At the end B, αgαin the energy becomes totαlly potentiαl. Total mechαnicαl energy remαins constαnt ( = mgh) αt αll points.
The energy of the body is grαduαlly used in doing work αgαinst the force of friction αt the point of suspension and αlso αgαinst friction of αir. The energy spent is converted into heαt. There is no violαtion of the lαw of conservαtion of energy. Due to decreαse in the energy of the bob, it αmplitude of oscillαtion decreαses with time and eventuαlly the bob comes to rest.
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