1) A Wimshurst machine just like in lab) is used to conduct some electrostatics
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Question
1) A Wimshurst machine just like in lab) is used to conduct some electrostatics periments. In one experiment (scenario 1 below) two identical and initially uncharged eXI pith balls held on wooden sticks) separately touch one electrode of the machine (one at a time) after it has been charged. Recall that pith balls are covered with a conducting coating such as graphite and Wimshurst machine electrodes hold an enormous amount of harge. In a second experiment (scenario 2) the machine is recharged and the pith balls allowed to discharge so that they are again neutral. Holding the pith balls in contact the experimenter brings them close to one of the charged electrodes, one ball is closer than the other, but doesn't let either ball touch the electrode. Contact between the pith balls is then broken while they are in the vicinity of the electrode harged electrode scenario 1 a) For each scenario describe the charged state of each of the pith balls in terms of whether it is like or unlike the electrode. Explain your reasoningExplanation / Answer
(a) Let us assume that the electrode is positively charged and pitch balls are each neutral.
In scenario 1, the two pitch ball are in contact with the electrode. Since the amount of charge on electrode is large, a positive charge is induced on the balls as charge flows through one body to other when placed in contact. And according to Coulomb's law, there will be a force of repulsion between the two. That is, the pitch balls are like charged to that of electrode.
In scenario 2, when the pitch balls are in contact with each other but not with the electrode, a negtive charge is induced on the ball closer to the electrode, and simultaneously similar charge is indued on the other pitch ball, because of the contact. So, in this case, both the balls are having unlike charge to that of eletrode.
When the two balls are not in contact with either, a negative charge is induced on left ball as positive charge on elctrode will try to attract the ball. This results in inducing a positive charge on the right ball as left ball also try to attract other. So, one ball is like charged while the other is unlike charged.
(b)
In Scenario 1, electrons will flow from pitch balls to the charged electrode because of which the balls become positively chraged (due to loss of electrons).
In Scenario 1, when the pitch balls are in contact, electrons flows from electrode to the left ball due to which a negative charge is developed on it, and similarly, electrons will flow from this ball to other ball in contact but the amount of flow is less than the flow of electrons from electrode due to less force of attraction.
When the pitch balls are not in contact, electrons will flow from eectrode and from right ball to the left ball and due to which a negative charge is induced on the left ball.
(c)
In system 1, Charge Q will be induced on both the balls.
In system 2, charge Q/r amount of charge willl be induced on left ball, where r is the distance from one ball to other. And a similar but oppsite charge will be there on right ball.
In system 3, charge Q/r will be on the left ball and Q/r^2 charge will be on the right ball, thought both the charges are different in magnitude and nature.
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