POST$-$LAB

Answer the following questions. Give a detailed explanation for each response.

a$.$ Can an object with a positive net charge attract a neutral object?

b$.$ Can a neutral object attract an object with a positive net charge?

Examine the representation of the charged plastic rod in Figure $21\mathrm{.}2$ on page $611({10}^{th}ed)$ of Four text. Is this an accurate representation of the charges present in the rod? If so$,$ explain why. If not, explain why not and propose a more accurate figure.

A longhaired cat is in need of some grooming. When it is combed, the cat looses $8{10}^{10}$ electrons.

a$.$ What is the sign and magnitude $($in Coulombs$)$ of the net charge on the cat?

b$.$ On the comb?

c$.$ It is reasonable to treat the cat as though it is made of water $,$ remember that there are $6{10}^{23}$ molecules in a mole$).$ Also assume that it has a mass of $9[kg].$ Approximately what fraction of the cat's electrons are removed to create this net charge? Comment on the size of this fraction.

$1{10}^{10}$ electrons are removed from a penny $(2\mathrm{.}5[g]).$ The same number is removed from a quarter $(5\mathrm{.}67[g]).$ Compare the magnitudes of the net charges on the two objects.

Shown below are three

a$.$ Find the net force on the $4[C]$ charge. Show your calculations.

b$.$ Now put an imaginary box around the two charges on the left as shown. Treat these charges as one object. What is the net charge on this object?

c$.$ What is the force $($magnitude and direction$)$ exerted on this object by the $4[C]$ charge? If the magnitude is zero state that explicitly, if not, explain how you determined your answer.

d$.$ Is your answer to part $($c$)$ consistent with Newton's Third Law? If not, resolve the inconsistency.

POST-LAB 1) Answer the following questions. Give a detailed explanation for each response. a. Can an object with a positive net charge attract a neutral object? b. Can Examine the representation of the charged plastic rod in Figure 21.2 on page 611 (10th ed) of your text. Is this an accurate representation of the charges present in the rod? If so, explain why. If not, explain why not and propose a more accurate figure. 3) A longhaired cat is in need of some grooming. When it is combed, the cat looses 8x1010 electrons. a. What is the sign and magnitude (in Coulombs) of the net charge on the cat? b. On the comb? c. It is reasonable to treat the cat as though it is made of water (18 [g/mol], remember that there are 6x1023 molecules in a mole). Also assume that it has a mass of 9[kg]. Approximately what fraction of the cat's electrons are removed to create this net charge? Comment on the size of this fraction. 4) 1 x 100 electrons are removed from a penny (2.5[g]). The same number is removed from a quarter (5.67[g]). Compare the magnitudes of the net charges on the two objects. 5) Shown below are three fixed charges. 1[m] -1[C] 2[m] 4[C] 1[C] a. Find the net force on the 4[C] charge. Show your calculations. b. Now put an imaginary box around the two charges on the left as shown. Treat these charges as one object. What is the net charge on this object? c. What is the force (magnitude and direction) exerted on this object by the 4[C] charge? If the magnitude is zero state that explicitly, if not, explain how you determined your answer. d. Is your answer to part (c) consistent with Newton's Third Law? If not, resolve the inconsistency.