Textbook Exercises on Electrostasis
Week Five Textbook Exercises
Geoffrey Anderson
PHY/101
December 9, 2014
Mr. Craig Spencer
Week Five Textbook Exercises
Chapter 22: Electrostatics
8) When combing your hair, you scuff electrons from your hair onto the comb. Is your hair then positively or negatively charged? How about the comb? -The hair becomes positively charged and the comb becomes negatively charged; since, the electrons went from your hair to the comb and the more electrons there is makes an object more negative.
18) It is relatively easy to strip the outer electrons from a heavy atom like that of uranium (which then becomes a uranium ion), but it is very difficult to remove the inner electrons. Why do you suppose this is so? -Outer electrons are loosely bound with the nucleus because of their larger distance from the nucleus, so they can be easily stripped off. In the case of the inner electrons, the opposite is true. They are more tightly bound because their closer to the nucleus, so they are more difficult to remove them.
52) You are not harmed by contact with a charged metal ball, even though its voltage may be very high. Is the reason similar to why you are not harmed by the greater than 1000ºC sparks from a Fourth of July sparkler? Defend your answer in terms of the energies that are involved. -Yes. The reason is similar, because the amount of energies involved in both cases is very small.
Chapter 23: Electric Current
46) In the circuit shown, how do the brightnesses of the identical lightbulbs compare? Which bulb draws the most current? What will happen if Bulb A is unscrewed? If Bulb C is unscrewed? -The brightness of Bulb A and Bulb B will be the same, while Bulb C will be twice as Bulbs A or B. Bulb C draws the most current. When Bulb A is unscrewed, Bulb C will glow as it had and Bulb B will not glow. If Bulb C is unscrewed, Bulb A and Bulb B will glow at the same brightness.
Chapter 24: Magnetism
15) One way to make a compass is to stick a magnetized needle
Geoffrey Anderson
PHY/101
December 9, 2014
Mr. Craig Spencer
Week Five Textbook Exercises
Chapter 22: Electrostatics
8) When combing your hair, you scuff electrons from your hair onto the comb. Is your hair then positively or negatively charged? How about the comb? -The hair becomes positively charged and the comb becomes negatively charged; since, the electrons went from your hair to the comb and the more electrons there is makes an object more negative.
18) It is relatively easy to strip the outer electrons from a heavy atom like that of uranium (which then becomes a uranium ion), but it is very difficult to remove the inner electrons. Why do you suppose this is so? -Outer electrons are loosely bound with the nucleus because of their larger distance from the nucleus, so they can be easily stripped off. In the case of the inner electrons, the opposite is true. They are more tightly bound because their closer to the nucleus, so they are more difficult to remove them.
52) You are not harmed by contact with a charged metal ball, even though its voltage may be very high. Is the reason similar to why you are not harmed by the greater than 1000ºC sparks from a Fourth of July sparkler? Defend your answer in terms of the energies that are involved. -Yes. The reason is similar, because the amount of energies involved in both cases is very small.
Chapter 23: Electric Current
46) In the circuit shown, how do the brightnesses of the identical lightbulbs compare? Which bulb draws the most current? What will happen if Bulb A is unscrewed? If Bulb C is unscrewed? -The brightness of Bulb A and Bulb B will be the same, while Bulb C will be twice as Bulbs A or B. Bulb C draws the most current. When Bulb A is unscrewed, Bulb C will glow as it had and Bulb B will not glow. If Bulb C is unscrewed, Bulb A and Bulb B will glow at the same brightness.
Chapter 24: Magnetism
15) One way to make a compass is to stick a magnetized needle
References: Hewitt, P.G. (2010). Conceptual Physics (11th ed.). St. Petersburg, FL: Pearson.