P6 LT1 - University Physics 14th ed summary of quiz part 1 PDF

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law is an equation that states that the electric flux in a closed region in space is equal to the enclosed charge over the permittivity of free space. GAUSS’S The product of the electric field and area is called the electric FLUX is a region in space produced by a charge that carries with it a force...

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1. law is an equation that states that the electric flux in a closed region in space is equal to the enclosed charge over the permittivity of free space. GAUSS’S 2. The product of the electric field and area is called the electric FLUX 3. is a region in space produced by a charge that carries with it a force. It is mathematically defined as force over charge. - ELECTRIC FIELD 4. The SI unit for the electric charge is ____________ - COULOMB 5. It is _________________ (true/false) that the direction of the electric field from a negative point charge is towards it. - TRUE 6. The SI unit for electric field is ___________________ N/C 7. If a Gaussian surface encloses a space that contains 1C positive charge and two 0.5C negative charge, the electric flux in that Gaussian surface is - zero 8. Because electric field has direction then therefore it is an example of ____________ quantity. VECTOR 9. If a Gaussian surface encloses a space that has no charge in it, the electric flux in that Gaussian surface is _______ - zero 10. It is _________________ (true/false) that Gauss's law provides a shortcut to direct integration if the Gaussian surface is symmetric - TRUE 11. Because electric flux does not indicate direction in space then therefore it is an example of scalar 12. If a Gaussian surface encloses a space that contains a positive and negative charge of the same magnitude, the electric flux in that Gaussian surface is _______ZERO 13. Three identical point charges of 2.0 µC are placed on the x-axis. The first charge is at

the origin, the second to the right at x = 50 cm, and the third is at the 100 cm mark. What are the magnitude and direction of the electrostatic force which acts on the charge at the origin? - 0.18 N Left 14. Two closely spaced metal sheets of the same area have equal but opposite charges. Both sheets are horizontally aligned in space with the top sheet having positive surface charge density while the sheet with negative charge density is at the bottom. What is the electric field in the region at the top of the positively charged sheet? - zero 15. Why is a spherical Gaussian surface appropriate when calculating the electric field of a point charge? The normal vector at any point on the sphere is parallel to the electric field of the point charge.

16. Three 3.0 µC charges are at the three corners of an square of side 0.50 m. The last corner is occupied by a -3.0 µC charge. Find the electric field at the center of the square. - 4.3x105 N/C 17. Two point charges q = 4.2 nC (negtive) and Q = 4.2 nC (positive) are separated by distance 3.5 mm. What is their electric dipole moment? 1.7 x 10^ -3 Cm (from q to Q)

18. A piece of plastic has a net charge of +2.00 µC. How many more protons than electrons does this piece of plastic have? 1.25x1013

19. An infinitely long nonconducting cylinder of radius R = 2.00 cm carries a uniform volume

charge density of 18.0 micro-Coulomb/cubic meter. Calculate the electric field at distance r = 1.00 cm from the axis of the cylinder. 10.2 x 10^3 N/C 20. if a conductor is in electrostatic equilibrium near an electric charge - The electric field on the surface of the conductor is perpendicular to the surface 21. "Two charges q1 = 2.0 nC and q2 = 9.0 nC are placed at (x = 2.0 m, y = 0) and (x = 0, y

= 8.0 m) respectively. What is the magnitude of the net electric field at the origin?" -1.3 x 10^18N/C

22. Which of the following does not affect electric flux? - shape of the source charge

23. If the electric flux through a Gaussian surface enclosing an unknown charge is -1.81 x 10^-8 N?m^2/C. What is the electric flux through the Gaussian surface if it encloses 1000 of these unknown charges? - 1.81 x 10^-5 N?m^2/C 24. Two charged objects are separated by a distance d. The first charge is larger in magnitude than the second charge. - The charges exert forces on each other equal in magnitude and opposite in direction. 25. What does it mean if the electric flux through a closed surface is negative? - The charge inside the closed surface is negative. 26. "If 3 N force is exerted on a positive charge due to an electric field of 5 N/C, what is the

value of the charge?" 0.6C 27. What is the electric field 7.0 m from a point charge q = 8.0 nC? 1.47 N/C

28. An infinitely long nonconducting cylinder of radius R = 2.00 cm carries a uniform volume charge density of 18.0 micro-Coulomb/cubic meter. Calculate the electric field at distance r = 1.00 cm from the axis of the cylinder. 10.2 x 10^3 N/C 29. "Two identical small charged spheres are a certain distance apart, and each one initially experiences an electrostatic force of magnitude F due to the other. With time, charge gradually leaks off of both spheres. When each of the spheres has lost half its initial charge, the magnitude of the electrostatic force will be" ¼ F 30. Where do charges on a conductor reside under electrostastic conditions? On the surface 31. What must be the charge of a 1.46 g particle for it to remain stationary when placed in a downward directed electric field of magnitude N/C? 21 micro-Coulomb (negative charge) 32. Three point charges are located at the following positions: Q1 = 2.00 µC at x = 1.00 m; Q2 = 3.00 µC at x = 0; Q3 = -5.00 µC at x = -1.00 m. What is the magnitude of the force on the 3.00-µC charge? - 5.40x10-2 N 33. Suppose a charge -Q is located 24 units to the left of the origin. Where should another charge +Q be placed so that the net electric field at the origin is zero? - 24 units right to the origin 34. A 5.0-C charge is 10 m from a small test charge. What is the magnitude of the electric field at the location of the test charge? 4.5x108 N/C 35. Consider a square which is 1.0 m on a side. Charges are placed at the corners of the square as follows: +4.0 µC at (0, 0); +4.0 µC at (1, 1); +3.0 µC at (1, 0); -3.0 µC at (0, 1). What is the magnitude of the electric field at the square's center? 1.1 ×105N/C 36. A spherical conducting sphere of radius R = 10 cm has total excess charge Q. What is the electric field inside the sphere? zero 37. Consider a spherical Gaussian surface of radius R centered at the origin. A charge Q is placed inside the sphere. -anywhere 38. If the electric field through a disk is doubled, how will the electric flux change? - The electric flux will be doubled since electric flux is directly proportional to the electric field. 39. "A non-conducting sphere of radius R = 7.0 cm carries a charge Q = 4.0 mC distributed

uniformly throughout its volume. At what distance, measured from the center of the sphere, does the electric field reach a value equal to half its maximum value?"3.5 and 9.9 40. An insulating sphere of radius R has a positive charge. At which region is the electric field at a maximum? r=R 41. It is _________________ (true/false) that the direction of the electric field from a positive point charge is inward and outward. false 42. A S pherical conducting sphere of radius R = 10 cm has total excess charge Q. What is

the electric field outside the sphere? - kQ/r^2 43. What is the direction of the electric field of a positive point charge? - radially outward 44. If a solid metal sphere and a hollow metal sphere of equal diameters are each given the same charge, the electric field (E) midway between the center and the surface is - zero for both

45. Two charges q1 = 2.0 nC and q2 = 9.0 nC are placed at (x = 2.0 m, y = 0) and (x = 0, y = 8.0 m) respectively. What is the magnitude of the net electric field at the origin? - 1.26 x 10^18

46. Consider two closely spaced and oppositely charged parallel metal plates. The plates are square with sides of length L and carry charges Q and -Q on their facing surfaces. What is the magnitude of the electric field in the region between the plates? Q/(epsilon naught)L^2

47. Which of the following is not always true about electric field lines?

Electric field lines are directed from positive to negative charge.

48. The normal vector of a disk (r = 10 cm) is parallel to a uniform electric field (E = 2.0 x 10^3 N/C). What is the flux through the disk? 49. It is _________________ (true/false) that the direction of the electric field from a positive point charge is towards it. false

50. At twice the distance from a point charge, the strength of the electric field is one-fourth its original value.

51. A spherical, non-conducting shell of inner radius = 10 cm (r1) and outer radius = 15 cm (r2) carries a total charge Q = 15 ?C distributed uniformly throughout the volume of the shell. What is the magnitude of the electric field at a distance r = 12 cm from the center of the shell? 2.87 x 10^6 N/C 52. A Styrofoam ball of mass 0.120 g is placed in an electric field of 6000 N/C pointing downward. What charge must be placed on the ball for it to be suspended? -196 nC 53. "What is the x-component of the electric field at (x = 1.2 m, y = -1.6 m) due to a point charge (q = -8.0 nC) at the origin?"

14 N/C

54. "Under electrostatic conditions, what is the configuration of the electric field just outside the surface of any charged conductor?" perpendicular to the surface 55. "When two point charges are a distance d part, the electric force that each one feels from the other has magnitude F. In order to make this force twice as strong, the distance would have to be changed to ______." d/2^1/2 56. Is it possible to have a zero electric field value between two positive charges along the line joining the two charges? "Yes, regardless of the magnitude of the two charges."

57. Which of the following is a vector quantity? Electric field 58. Q1 = 6.0 nC is at (0.30 m, 0); Q2 = -1.0 nC is at (0, 0.10 m); Q3 = 5.0 nC is at (0, 0). What is the direction of the net force on the 5.0 nC charge? 56 above -x axis 59. The electric flux through a Gaussian surface enclosing an unknown charge is 100 N?m^2/C. What is the value of the charge? 0.89 nc < tama yan 60. A non-conducting sphere of radius R = 7.0 cm carries a charge Q = 4.0 mC distributed uniformly throughout its volume. At what distance, measured from the center of the sphere, does the electric field reach a value equal to half its maximum value? 3.5 cm and 9.9 cm 61. What is the electric field 200.0 m from an infinite line charge with charge density 0.001 C/m? 89900 N/C 62. How much force does a 5 C charge experience in a region of uniform electric field E = 100 N/C? 500 N...