A book is at rest on the top of a table. A student makes the following claim: “an attractive electromagnetic force is exerted on the book from the table, and this force can also be classified as the normal force.” Which of the following states correctly justifies the student’s claim? A) the claim is correct because the charged particles of the table excerpt a downward attractive force on the changed particles of the book.
B) the claim is correct because the charges particles of the table expect a downward repulsive force on the charges participles of the book
C) the claim is incorrect because the charges of the table except an upward repulsive force on the charges participles of the book.
D) the claim is incorrect because the charges particles of the table excerpt an upward attractive force on the charges particles of the book.

In the future, people will only enjoy one sport: electrodisc. in this sport, you gain points when you cause metallic discs hovering on a field to exchange charge. you are an electrodisc player playing the popular four disc variant. the disks have charges of qa = −8.0 µc, qb = −2.0 µc, qc = +5.0 µc, and qd = +12.0 µc. (1) you bring two disks together and then separate them. you measure the resulting charge of these two disks and find that it is +5.0 µc per disk. which two disks did you bring together? (a) a and b (b) a and c (c)a and d (d)b and c(e) b and d (f) c and d. (2) you bring three disks together and then separate them. you measure the resulting charge of these three disks and find that it is +3.0 µc per disk. which three disks did you bring together? a, b, and c (a) a, b, and d (c) a, c, and d (d) b, c, and d. (3) given the resulting charge of each disk measured in (b) is +3.0 µc, how many electrons would you need to add to a disk of this charge to electrically neutralize it? electrons