Practice Exam I: PHYS 1302Name___________________________________MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.1)An atomic nucleus has a charge of +40e. An electron is 10-9 m from the nucleus. What is theforce on the electron?A)9.2 nNB)6.8 nNC)3.7 nND)2.9 nNE)1000 C1)FIGURE 19-142)Three point charges of magnitude +2.0 µC, +3.0 µC, +4.0 µC are located at the corners of a triangleas shown in Figure 19-14 The resultant force acting on the +4.0 µC charge is given byA)1.8 N at 97° with the +y-axis.B)2.7 N at 97° with the +y-axis.C)3.9 N at 97° with the +x-axis.D)2.7 N at 97° with the +x-axis.E)3.9 N at 97° with the +y-axis.2)3)A metal sphere of radius 10 cm carries a charge of +2.0 µC. What is the magnitude of the electricfield 5.0 cm from the sphere's surface?A)8.0 × 107 N/CB)4.0 × 109 N/CC)4.0 × 105 N/CD)8.0 × 105 N/CE)4.0 × 107 N/C3)4)A +5.0-µC charge is moved from a negative to a positive plate of a parallel plate capacitor. Inmoving this charge 0.30 mJ of energy is used. What is the potential difference between the platesof this capacitor?A)60 VB)23 VC)55 VD)0 VE)81 V4)1Practice Exam 1 - Dr Anthony Timmins5)A 4.0-µC charge is situated at the origin of an xy-coordinate system. What is the potentialdifference between a point x = 4.0 m and y = -4.0 m because of this charge?A)-18 × 103 VB)0 VC)-36 × 103 VD)36 × 103 VE)18 × 103 V5)6)A 100-V DC signal is applied to a series circuit composed of four equal resistors 10 Ω each. Whatis the voltage across each resistor?A)20 VB)25 VC)15 VD)10 VE)50 V6)FIGURE 21-197)Four capacitors are connected across a 90-V DC source as shown in Figure 21-19. What is thecharge on the 4.0-µF capacitor?A)90 µCB)120 µCC)68 µCD)240 µCE)180 µC7)8)An electron moves with a speed of 8.0 × 106 m/s along the +x-axis. It enters a region where thereis a magnetic field of 2.5 T, directed at an angle of 60° to the +x-axis and lying in the x-y plane.Calculate the magnitude of the magnetic force on the electron.A)3.2 × 10-10 NB)2.8 × 10-12 NC)0 ND)3.2 × 10-12 NE)2.8 × 10-10 N8)9)The magnetic field at a certain distance from a wire carrying 2-A current is 4 µT. What will bethe magnetic field if the current in the wire is doubled?A)2 µTB)8 µTC)6 µTD)4 µTE)10 µT9)210)How much current must pass through a 400 turn coil 4.0 cm long to generate a 1.0-T magneticfield at the center?A)13 AB)80 AC)40 AD)22 AE)0.013 A10)11)Electrical and gravitational forces follow similar equations with one main difference:A)Electrical forces obey the inverse square law and gravitational forces do not.B)Electrical forces attract and gravitational forces repel.C)Gravitational forces are always attractive but electrical forces can be attractive orrepulsive.D)Gravitational forces obey the inverse square law and electrical forces do not.E)Electrical forces repel and gravitational forces attract.11)12)An equipotential surface must beA)randomly oriented with respect to the electric field.B)parallel to the electric field at any point.C)equal to the electric field at any point.D)perpendicular to the electric field at any point.12)13)The length of a certain wire is kept same while its radius is doubled. What is the change in theresistance of this wire?A)It is quadrupled.B)It is reduced by a factor of 4.C)It is doubled.D)It is reduced by a factor of 8.E)It is reduced by a factor of 2.13)14)When you double the number of windings in a solenoid keeping all other parameters (radius,length and current) fixed, the magnetic field at the center of the solenoid willA)be reduced to one-fourth as much.B)be reduced to half as