ATTENTION: EXPERT
Following questions are from our school SCIENCE book's CHAPTER 11(ELECTRIC CHARGES AT REST) OF DAV CMC, PROVIDED BY OUR SCHOOL. THIS CHAPTER IS NOT AVAILABLE AT OUR MERITNATION SCHOOL.
SO YOU ARE REQUESTED TO KINDLY PROVIDE ME THE ANSWER OF THE QUESTIONS AS MENTIONED BELOW:-
Q1. A glass rod is rubbed against a silk cloth and an ebonite rod is rubbed against a piece of flannel. List the pairs which have (a) similar (b) dissimilar charges on them.
Q2. A chrged drinkinG plastic straw is brought near another similar suspended straw that is (a) also similarly charged (b) uncharged. Explain what we would observe in each case and why.
Q3. Describe a simple experiment to show that the total charge on a pair of objects rubbed together is zero.
Q4. Why do we say that ' charges are always produced in pairs'?
Q5. State advanteages of lightninig.
Q6. Is it important to have a very good contact between the lower end of a lightning conductor and the earth? if so, why?
Q7. A charged object is found to lose its charge when touched. Explain, why?
Q8. What can we say about the sign of the charge acquired by an object when it is charged by a positively charged rod through (i) conduction (ii) induction?
Q9. Can we say that a charged object attracts an uncharged object by first charging it by induction ? Explain your answer.
Due to paucity of time it would not be possible for us to provide the answers to all your queries. We are providing solutions to some your good queries. Try solving rest of the questions yourself and if you face any difficulty then do get back to us.
(1) similar charges: 1. Positive charge- glass rod and flannel
2. Negative charge- silk cloth and ebonite rod
(2) in first case when charged straw brought near similar charged straw then repulsion will occur between these straws. and when charged straw is brought near to dissimilar charged straw, then attraction will be observed because like charges repel and unlike charges attract.
(4) charges are always produced in pairs to neutral the total charge or to maintain the total charge to be zero.
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