Electricity and Magnetism #1 Free Response Question Solutions - AP Physics C 1998 Released Exam

The video tutorial walks through solutions to an AP Physics C electricity and magnetism problem. It covers the setup of charged spheres, drawing free body diagrams, analyzing forces, and solving for unknown charges. The tutorial also explores the effects of replacing a non-conducting sphere with a conducting one, using Gauss's law to find the electric field around a charged tube, and calculating the electric force and work done on a sphere.

What is the initial charge on sphere A?

• 200 micro coulombs

• 100 micro coulombs

• 150 micro coulombs

• 120 micro coulombs

Which force acts directly downward on sphere B1?

• Gravitational force

• Tension force

• Electric force

• Magnetic force

What is the value of Coulomb's constant used in the calculations?

• 7.99 x 10^9 N m²/C²

• 8.85 x 10^9 N m²/C²

• 8.99 x 10^9 N m²/C²

• 9.81 x 10^9 N m²/C²

What is the mass of sphere B1?

• 0.025 kg

• 0.050 kg

• 0.075 kg

• 0.100 kg

What is the angle of the thread with the vertical when sphere B1 is hanging?

• 40 degrees

• 30 degrees

• 20 degrees

• 10 degrees

What happens to the angle of the thread when sphere B2 is conducting?

• The angle increases

• The angle decreases

• The angle remains the same

• The angle becomes zero

What is the linear charge density of the tube?

• 10 micro coulombs per meter

• 0.01 micro coulombs per meter

• 0.10 micro coulombs per meter

• 1.0 micro coulombs per meter

According to Gauss's Law, what is the electric field outside the tube proportional to?

• R^2

• 1/R^2

• R

• 1/R

What is the distance from the center of the tube to sphere A when calculating the electric force?

• 0.5 meters

• 1.0 meters

• 1.5 meters

• 2.0 meters

What is the work done to move sphere A closer to the tube?

• 0.45 joules

• 0.25 joules

• 0.15 joules

• 0.35 joules