Physics Lessons
University of the Philippines
College of Science
PHYSICS 72
SET A
Second Semester 2010-2011 First Long Examination
National Institute of Physics
2nd Sem AY 2010-2011
Physics 72
INSTRUCTIONS: Choose the best answer and shade the corresponding circle on your answer sheet. To change your answer, cross-out and sign your original answer and then shade your new answer. No computational devices allowed (e.g. calculators, mobile phones). Following instructions is part of the exam. Useful formulas: Area Sphere (radius = r) Cylinder (radius =r, height = h) 1. Volume Useful constants: e me εo k -1.60 x 10-19 C 9.1 x 10-31 kg 8.854 x 10-12 C2/Nm2 8.988 x 109 Nm2/C2
Consider three identical metal spheres, A, B, and C. Sphere A carries a charge of 2.0 µC; sphere B carries a charge of -6.0 µC; and sphere C is neutral. Spheres A and B are touched together and then separated. Spheres B and C are then touched and separated. What will be the new net charge of sphere C? A. -6.0 µC B. -2.0 µC C. 0 D. -1.0 µC E. +4.0 µC Charges Q1 = q and Q2 = +9q are placed as shown below. Of the five positions indicated by the numbered dots, at which point is the electric field E zero? Points 2, 3 and 4 have equal spacing in between Q1 and Q2.
2.
A. B. C. D. E. 3.
1 2 3 4 5
An electric dipole is released from rest in a uniform electric field with the orientation shown. Which of the following correctly describes the rotation and the net force on the dipole? A. No rotation; net force is zero B. Rotation is clockwise; net force is zero C. Rotation is counterclockwise; net force is zero D. Rotation is clockwise; net force is non-zero E. Rotation is counterclockwise; net force is non-zero
1|A
National Institute of Physics
2nd Sem AY 2010-2011
Physics 72
4.
Five particles of the same mass are released into a region of uniform electric field. The numbered lines show the paths taken by the five particles. A particle with a charge +6Q follows path 5 while
College of Science
PHYSICS 72
SET A
Second Semester 2010-2011 First Long Examination
National Institute of Physics
2nd Sem AY 2010-2011
Physics 72
INSTRUCTIONS: Choose the best answer and shade the corresponding circle on your answer sheet. To change your answer, cross-out and sign your original answer and then shade your new answer. No computational devices allowed (e.g. calculators, mobile phones). Following instructions is part of the exam. Useful formulas: Area Sphere (radius = r) Cylinder (radius =r, height = h) 1. Volume Useful constants: e me εo k -1.60 x 10-19 C 9.1 x 10-31 kg 8.854 x 10-12 C2/Nm2 8.988 x 109 Nm2/C2
Consider three identical metal spheres, A, B, and C. Sphere A carries a charge of 2.0 µC; sphere B carries a charge of -6.0 µC; and sphere C is neutral. Spheres A and B are touched together and then separated. Spheres B and C are then touched and separated. What will be the new net charge of sphere C? A. -6.0 µC B. -2.0 µC C. 0 D. -1.0 µC E. +4.0 µC Charges Q1 = q and Q2 = +9q are placed as shown below. Of the five positions indicated by the numbered dots, at which point is the electric field E zero? Points 2, 3 and 4 have equal spacing in between Q1 and Q2.
2.
A. B. C. D. E. 3.
1 2 3 4 5
An electric dipole is released from rest in a uniform electric field with the orientation shown. Which of the following correctly describes the rotation and the net force on the dipole? A. No rotation; net force is zero B. Rotation is clockwise; net force is zero C. Rotation is counterclockwise; net force is zero D. Rotation is clockwise; net force is non-zero E. Rotation is counterclockwise; net force is non-zero
1|A
National Institute of Physics
2nd Sem AY 2010-2011
Physics 72
4.
Five particles of the same mass are released into a region of uniform electric field. The numbered lines show the paths taken by the five particles. A particle with a charge +6Q follows path 5 while