Electric Field and Potential Questions and Answers

Two equally charged, identical metal spheres A and B repel each other with a force 'F'. The spheres are kept fixed with a distance 'r' between them. A third identical, but uncharged sphere C is brought in contact with A and then placed at the mid-point of the line joining A and B. The magnitude of the net electric force on C is A. F B. 3F/4 C. F/2 D. F/4

The distance between the K+ and Cl- ions in KCl is 2.8 x 10^-10. Find the energy required to separate the two ions to an infinite distance apart, assuming them to be point charges initially at rest. The elemental charge is 1.6 x 10^-19C and the Coulomb constant is 8.99 x 10^9N m²/C² 1. 6.77 eV 2. 5.14 eV 3. 709.1 eV 4. 101.3 eV 5. 8.91 eV 6. 4.37 eV

Seventeen coulombs of positive charge flow from the +9 V positive terminal of a battery to the negative terminal at 0 V. (a) What is the change in the potential energy of the charge?

Draw and label a model below to show why some clothes stick together when they come out of the dryer. In your model: Assume the shirt is neutral but the socks have picked up a charge during drying Draw and label two atoms in the zoom-in circle - one atom in the sock and one atom in the shirt -- to show what is happening to the atoms when they are close together (4 pts.) Draw arrows to show the direction of electrostatic forces between the shirt and sock atoms (1 pt.)

A proton and an electron are 1 meter apart. If the single electron is replaced by 2 electrons, the force between the charges is one quarter as strong half as strong twice as strong. four times as strong.

You place a single electron and a single proton in an electric field. The acceleration of the electron is the acceleration of the proton. equal to and in the same direction as greater than and in the same direction as equal to and in the opposite direction as greater than and in the opposite direction as

Which of the following statement is correct regarding the Coulomb's forc and Biot-Savart's force? (a) Electrostatic force is along the displacement vector joining the source a the field but magnetic force is perpendicular to the plane containing the displacement vector and source. (b) There is an angle dependence in the Biot-Savart's law, which is present in Coulomb's law. (c) Biot-Savart's law can be expressed in vector form but Coulomb's law cannot be expressed in vector form. (d) Biot-Savart's law is applicable in all medi but Coulomb's law is applicable only in medium which can be polarised.

In free space, a particle A of charge 1 μC is held fixed at a point P. Another particle B of the same charge and mass 4µg is kept at a distance of 1 mm from P. if B is released, then its velocity at a distance of 9mm from P is: 9 x 10⁹ Nm² C-2 1 2.0 × 10³ m/s 3.0 x 10¹ m/s 1.5 × 10² m/s 1.0m/s

Two 2.5-cm-diameter disks face each other, 2.0 mm apart. They are charged to ± 15 nC. What is the electric field strength between the disks? A proton is shot from the negative disk toward the positive disk. What launch speed must the proton have to just barely reach the positive disk?

Electric Field. Find the electric field between two oppositely charged parallel metal (capacitor) plates. The charge on a capacitor plate is Q = 20 μC. The area of each plate is 2.5 m². The distance between plates is 0.4 m.

The metal plate on the left in fig. carries a surface charge of + per unit area. The metal plate on the right has a surface charge of -20 per unit are. It is assumed that the plates are large and the central plate is connected to zero. Then the charge densities on the left and right surface of the central plate are, respectively.

A uniform electric field is oriented in the -z direction. The magnitude of the electric field is 6500 N/C. (a) How will the equipotential surfaces associated with this electric field be oriented? parallel to the xy plane parallel to the xz plane parallel to the yz plane (b) Consider two of the equipotential surfaces; one with a potential of 13 V and the other with a potential of -16 V. What is the separation between these two surfaces? mm

The equipotential surfaces surrounding a point charge are concentric spheres with the charge at the center. If the electric potential of two such equipotential surfaces that surround a point charge +1.49 x 10-8 C are 205 V and 72.5 V, what is the distance between these two surfaces? m

A round storm cell covers an area with a diameter of 1km. The clouds that make up the cell range in altitude from 867m to 5309m. The clouds are charged negative on the bottom and positive on the top due to some incompletely understood mechanism (possibly friction between ice crystals and the air). The surface of the Earth acquires a positive charge by induction as the negative charges are driven deeper into the Earth. Determine... a. The direction of the electric field within the clouds of the storm cell. b. The direction of the electric field in the space between the bottom of the cell and the surface of the Earth. c. The capacitance of the storm cell capacitor. d. The capacitance of the space between the bottom of the cell and the surface of the Earth (aka the Earth-cloud capacitor). e. Considering that the air breaks down at an electric field strength of 3,000,000 V/m, what is the maximum voltage difference between the cloud and the ground that the air can sustain before lighting would strike? f. The maximum charge that can be stored in the Earth-cloud capacitor.

8. A metal sphere as a charge of +2.3 x 10-6C and lies 2 meters away from another metal sphere of unknown charge. If the attractive force present between the spheres is 0.05 N, what is the charge on the second sphere?

An electron is separated from another point charge by a distance of 5 centimeters. The electrostatic force between them is -9.24 x 10-26 C. What is that point charge? (Coulomb's constant is 9.0 x 109 Nm²/C2; e = -1.602 x 10-19 C) Select one: a. cannot be determined O b. a neutron O c. an electron d. a proton

In the image below, you have a before and after case.. Initially q1 and q2 are closer together (top image). The charge q1 is being held stationary and is not allowed to move. But q2 is released and allowed to move. In the final image you can see where q2 has moved after being released. Look at the Initial set up and the Final set up. Is the change in the Kinetic Energy of q2 positive or negative? Make sure to think about the signs of the charges and their relative distances.

As an electron moves in the direction the electric field lines 1.it is moving from low potential to high potential and gaining electric potential energy. 2.it is moving from low potential to high potential and losing electric potential energy. 3.it is moving from high potential to low potential and gaining electric potential energy. 4.it is moving from high potential to low potential and losing electric potential energy. 5.both its electric potential and electric potential energy remain constant.

A charge Q=1.2 µC sits somewhere inside a cube of side length 1 = 3.7 cm.

Two small Styrofoam balls that are separated (between their centers) by 4 cm experience a force of attraction of 15 N. If the balls are separated by 8 cm, the force between them would be ___ N.

A droplet of ink in an ink-jet printer contains a charge of 1.5 x 10^-10 C. It experiences a force to put it on a piece of paper of 1.0 x 10^-4 N. The electric field that the droplet experiences is ___ N/C.

A large, flat, horizontal sheet of charge has a charge per unit area of 30 pC/m^2. The magnitude of the electric field just above the middle of the sheet equals: a. 1.695 x 10^2 N/C b. 1.695 N/C c. 1.695 x 10^-1 N/C d. 1.695 x 10³ N/C

Three point charges q1 = 21 x 10-6 C, q2 =28 x 10-6 C and q3 = -10 x 10-6 C are arranged as shown in figure below. If separation distances shown in figure below are r12=0.6 m and r13=0.2 m, then find the magnitude of the net electric force on the charge at the origin q1. (Consider ke -9 x 109 N.m²/C²)

An electron with a charge value of 1.6 x 1019 C is moving in the presence of an electric field of 400 N/C. What force does the electron experience? Select one: a. 1.9 x 10-21 N b. 2.3 x 10-22 N c. 4.0 x 10-17 N d. 6.4 x 10-17 N e. 4.9 × 10-17 N

Place the letter of the diagram that best represents the charge on an electroscope during each of the procedures described. A positively-charged rod is brought near a positively-charged electroscope. A positively-charged rod is brought near, but not touching an uncharged electroscope. A positive rod is brought near a neutral electroscope, and the electroscope is charged by induction. A negatively-charged rod is brought near a neutral electroscope. An electroscope is charged by conduction by a positive rod. A glass rod is charged positively by rubbing it with silk. The silk is touched to a neutral electroscope. A metal rod is brought in contact with the positively-charged electroscope.

A point charge of q₁ = 4.00 x 10^-5C is separated by a distance of 1.0 m from a second negative point charge of q2 = -5.00 x 10^-5 C. What is the net electric field due to the charges at a point P located between the charges 0.75 m from charge q₁?

A -0.06 C charge that moves downward is in a uniform electric field with a strength of 200 N/C. What is the magnitude and direction of the force on the charge? 12 N up 12 N down 3333 N up 3333 N down

Ink-jet printers spray charged drops of ink onto paper. An electric field in the printer head produces a force on the ink drops. (a) Find the electric field strength that produces a force of 2.8 x 104 N on a drop having a charge of 1.6 x 10-1¹0 C. (b) If the electric field were increased in strength by 10%, by what factor would the force on the charged drops increase?

Gordon, the night custodian, dusts off a classroom globe with a feather duster, causing the globe to acquire a charge of -6.0 x 10-⁹ C. What is the magnitude and direction of the electric field at a point 0.45 m from the center of the charged globe?

What is the electrostatic force between the balloon with a charge of +5.70x10^-5 C and a comb with a charge of -2.5x10^-4 C if they are separated by a distance of 2.0x10^-2 m? *

A positive charge of 2.0 C and a positive charge of 3.0 C are separated by 80 m. What is the magnitude of the force between the two charges? a 5.4 X 10⁸ N b 4.5 x 10⁹ N c 6.75 x 10⁸ N d 1.4 x 10⁷ N e 8.4 x 10⁶ N

If two identical charges are brought to within 35 m of each other experience an electric force 1.54 x 10⁶N. What is the value of their charge?

A proton is moving away from a fixed proton attached to a piece of metal in interstellar space and the proton moves a distance of 2000 m. What work was done on the moving proton? Recall that W = Fd.

What is electrostatic force between a 55.0-nC charge and a 3720-μC charge that are 0.125-m apart?

35. A balloon becomes negatively charged when it is rubbed by a piece of fur. Then it is placed on a wall and appears to be attracted to the wall. Which of the following is NOT taking place. A. The balloon holds onto electrons better than fur does. B. The balloon is charged by friction C. The fur loses electrons and becomes positively charged. D. The wall becomes positively charged when it loses electrons to the balloon. E. The balloon sticks to the wall because of electrostatic attraction.

36. A particle with a charge of 2.0 x 10^-4 is placed r meters from another particle with charge q. Which of the following would result in the greatest electrostatic force? A.q=4.0 x 10^4 Cr=0.05 m B. q= 8.0 x 10^-4 Cr= 0.05 m C. q= 4.0 x 10^-4 C r = 0.20 m D. q = 8.0 x 10^-4 C r = 0.20 m E. q=1.0 x 10^4 Cr = 0.20 m

A beam of particles enters a uniform electric field, as shown below. The beam consists of the following particles: Particle 4, with mass m and charge +q, particle B. with mass 2m and charge +q, particle C, with mass m and charge -q, and particle D, with mass 2m and charge -q. On the diagram, indicate the motion of each of the particle types as the beam enters the field. This should be a qualitative sketch - you'll be graded on correctly indicating which particle streams separate, and in which directions, not on the exact correctness of any curves. Make sure your diagram is clearly labeled, and provide an explanation for the motion of each particle type.

A 2.6 mm -diameter sphere is charged to -4.6 nC. An electron fired directly at the sphere from far away comes to within 0.37 mm of the surface of the target before being reflected. What was the electron's initial speed? At what distance from the surface of the sphere is the electron's speed half of its initial value? What is the acceleration of the electron at its turning point?

Anegatively-charged balloon is brought near to a neutral, conducting sphere. When it is held near, what does the charge distribution on the metal sphere look like?

An atomic nucleus contains 56 protons, for iron. Which force would this nucleus apply on an electron at a distance of 10x10^-12 m? A. 0.65 x 10^-4 N B. 0.02 × 10^-4 N C. 1.3 x 10^-4 N D. 72.8 × 10^-4 N

A proton and an electron are placed in a uniform electric field in empty space. The particles are placed very far apart, so neither feels the effect of the other. Which particle will experience a greater acceleration in this electric field? a. The proton b. The electron c. Both will experience the same magnitude of acceleration. d. Not enough information

A positive charge is located at x = 0. When a negative charge is placed at x = 10 cm, what happens to the electric field lines between the charges? * A. The electric field lines become denser between the charges. 1 pc B. The electric field lines become denser between the charges. C. The electric field lines remains same between the charges. D. The electric field lines will be zero between the charges.

A conductor has no charge initially. A positively charged rod is brought near, but not touching, the left side of the conductor. The right side of the conductor is then briefly connected to ground. the rod is then removed. The conductor will be: A. negatively charged on the left side and positively charged on the right side B. negatively charged all over C. neutral all over D. positively charged on the left side and negatively charged on the right side E. positively charged all over

12. A proton is placed in a uniform electric field of 2.75 x 10³ N/C. Recall that a proton has a charge of 1.60 x 10-¹⁹ C and a mass of 1.67 x 10-27 kg. a. Calculate the magnitude of the electric force felt by the proton. b. Calculate the proton's acceleration.

An insulating rod carries + 2.0 Nc of charge. After rubbing it with a material, you find it carries -3 Nc of charge. How much charge was transferred to it? A. -5 Nc B. -3 Nc C. -1 Nc D. + 2.0 Nc

A constant electric field is (4.5 x 10^5 N/C)ŷ. In which direction is the force on a -20 nC charge placed in this field? A. The direction of the force is in the - X (force field) direction B. The direction of the force is in the + X (force field) direction C. The direction of the force is in the -ŷ direction. D. The direction of the force is in the +ŷ direction.

Two plastic spheres with uniform charge repel each other with a force of 10 N. If you remove the charge from one sphere, what will be the force between the spheres? * A. The force will be 15 N. B. The force will be 10 N. C. The force will be 5N. D. The force will be zero.

An electron (charge -e) is located at a distance r away from a carbon nucleus (charge +6e). Which of the following statements is true about the relative force magnitude between the electron and carbon nucleus? a. Both particles exert an equal force on each other. b. The electron exerts a larger force on the carbon nucleus. c. The carbon force exerts a larger force on the electron. d. Not enough information

What rule can you develop for the direction of the electric field due to positive and negative charges? Electric field lines always point away from a charge Electric field lines always point towards from a charge Electric field lines point away from negative charges and towards positive charges Electric field lines point away from positive charges and towards negative charges It depends on how much charge you have The direction of an electric field depends on the magnitude of charge

In Newton's law of universal gravitation, the force between two masses is proportional to the product of the two masses. What plays the role of mass in Coulomb's law? A. the electric charge B. the electric dipole C. the electric monopole D. the electric quadruple