What physics principle or principles lead to a theoretical prediction that a U-tape and an L-tape should have opposite charges? Check all that apply.The superposition principle Newton's second law Retardation Coulomb's law The principle of relativity Conservation of charge

19.A thin circular sheet of glass of diameter 6 meters is rubbed with a cloth on one surface, and becomes charged uniformly. A chloride ion (a chlorine atom which has gained one extra electron) passes near the glass sheet. When the chloride ion is near the center of the sheet, at a location 0.5 mm from the sheet, it experiences an electric force of 6e-15 N, toward the glass sheet. In this problem, use the value 0 = 8.85e-12 C2/(Nm2)It will be useful to you to draw a diagram on paper, showing field vectors, force vectors, and charges, before answering the following questions about this situation.

(c) How much charge is on the surface of the glass disk? (give amount, including sign, and correct units)

6.Charged tapeA strip of invisible tape 12 cm by 2 cm is charged uniformly with a total net charge of 4 10-8 coulomb and hangs vertically.(a) Divide the strip into three sections each 4 cm high by 2 cm wide, and use numerical summation to calculate the magnitude of the electric field at a perpendicular distance of 3 cm from the center of the tape. (Hint: Recall that the Pythagorean theorem in three dimensions has the form d2 = x2 + y2 + z2. E =

(b) Divide the strip into eight sections each 3 cm high by 1 cm wide, and use numerical summation to calculate the magnitude of the electric field at a perpendicular distance of 3 cm from the center of the tape. E = (c) Which of the following statements are true? (Select all that apply.) Using 8 pieces gives a more accurate result than using 3 pieces It is better to use more, smaller pieces, because each piece is more like a point charge Using fewer pieces reduces the error Using more than 8 pieces would make the calculation more accurate Using more than 8 pieces would not make the calculation more accurate Using 3 pieces gives a more accurate result than using 8 pieces

17. In a cathode-ray tube (CRT), an electron travels in a vacuum and enters a region between two "deflection" plates which have equal and opposite charges. The dimensions of each plate are 12 cm by 4 cm, and the gap between them is 2.5 mm (not to scale in the diagram).

During a 0.001 s interval while it is between the plates, the change of the momentum of the electron is kg m/s.

What is the electric field between the plates? Hint: remember the Momentum Principle (the relationship between Impulse and change in momentum.)

= < , , > N/C

What is the charge (both magnitude and sign) of the upper plate?

q = C