Exam 17: Current and Resistance Electric Current: Part A

The charge per unit length on an insulator is 6.2 μC/m.On a 2.0-m length of this material,what is the difference in the number of electrons and the number of protons?

About how many electrons are in 0.3 gram of water (H₂O)?

A conducting spherical shell of inner radius And outer radius Has a charge Q on it.The flux through a concentric spherical surface of radius Is )An additional charge,also Q,is then added to the sphere.What is the change in flux through a concentric spherical surface of radius When the additional charge is placed on the conducting shell?

If two 1.0-C charges have a force between them of 1.0 N,what is their separation?

Two identical spheres each carry a charge of −40.0 µC.The spheres are separated by a distance of 2.00 m.What is the electric force between the spheres? (k_e = 8.99 × 10⁹ N·m²/C²)

Object A has a charge q on it,object B has a charge q on it,and object C has a charge 2q on it.These charges are arranged,one each,at the vertices of an equilateral triangle.Which charge has the greatest magnitude electric force on it?

A proton initially moves left to right long the x axis at a speed of 2.00 × 10³ m/s.It moves into an electric field,which points in the negative x direction,and travels a distance of 0.300 m before coming to rest.If the proton's mass and charge are 1.67 × 10−²⁷ kg and 1.60 × 10−¹⁹ C,respectively,what is the magnitude of the electric field?

We have an initially uncharged hollow metallic sphere with radius of 5.0 cm.I place a small object with a charge of +40 µC at the center of the sphere through a hole in the surface.Find the electric field present at a point 10 cm from the sphere's center.(k_e = 8.99 × 10⁹ N⋅m²/C²)

An electron is sent at high speed toward a gold nucleus (charge +79e).What is the electrical force acting on the electron when it is 3.0 × 10−¹³ m away from the gold nucleus? (e = 1.6 × 10−¹⁹ C,k_e = 8.99 × 10⁹ N·m²/C²)

The electric field in a cathode ray tube is supposed to accelerate electrons from 0 to 1.60 × 10⁷ m/s in a distance of 4.00 cm.What electric field is required? (m_e = 9.11 × 10−³¹ kg and e = 1.60 × 10−¹⁹ C)

If the distance between two point charges is quadrupled,the mutual force between them will be changed by what factor?

A charge Q accumulates on the hollow metallic dome,of radius R,of a Van de Graaff generator.A probe measures the electric field strength at various points outside the sphere surface.If the probe is initially at a distance 3R from the sphere's center and then is moved to 5R,by what factor will the electric field reading change?

A charge Q accumulates on the hollow metallic dome,of radius R,of a Van de Graaff generator.A probe measures the electric field strength at various points outside the sphere's surface.By what factor will the electric field value at the 2R distance be changed if the charge value were increased to (5/3)Q?

A Van de Graaff generator has a spherical dome of radius 12 cm.Operating in dry air,where "atmospheric breakdown" is at E_max = 3.0 × 10⁶ N/C,what is the maximum charge that can be held on the dome? (k_e = 8.99 × 10⁹ N⋅m²/C²)

Charges of 4.0 µC and −6.0 µC are placed at two corners of an equilateral triangle with sides of 0.20 m.At the third corner,what is the electric field magnitude created by these two charges? (k_e = 8.99 × 10⁹ N·m²/C²)

Two point charges are 4 cm apart.They are moved to a new separation of 8 cm.By what factor does the resulting mutual force between them change?

A spherical volume of space has an electric field of intensity 170 N/C directed radially outward from it surface of radius 0.600 m.What is the net charge enclosed within this surface?

A ring of charge of radius r₀ lies in the x-y plane with its center at the origin.The charge counterclockwise from θ = 0º to θ = 180º is uniformly distributed with the total charge equaling Q.The charge counterclockwise from θ = 180º to θ = 360º is uniformly distributed with the total charge for this half of the ring equaling -Q.What is the direction of the electric field on the z-axis at the position (x,y,z)= (0,0,​r₀)?

Q₁ has 27 electric field lines radiating outward and Q₂ has 11 field lines converging inward.What is the ratio Q₁/Q₂?

Five equal negative charges are uniformly spaced in a semicircular arc of radius r₀ with its center at the origin.The charges positions in polar coordinates are given by (r₀,θ​_i),where the values of θ​_i are 0°,45°,90°,135°,and 180°.At the position (x,y)= (r₀,-r₀)in the 4th quadrant,which statement best describes the direction of the resulting electric field?