College Physics II: Module 3 & Module 4

2.4N to the left

A -4.0-µC charge is located 0.30 m to the left of a +6.0-µC charge. What is the magnitude and direction of the electrostatic force on the positive charge?

Both objects will attract each other.

A charged conductor is brought near an uncharged insulator. Which one of the following statements is true?

300

A conducting sphere has a net charge of -4.8 x 10-17 C. What is the approximate number of excess electrons on the sphere?

4.0uC

A metal sphere has 26.0μC and another identical one has -18.0μC on it. The charge on each after being brought into contact is ________.

10.0μC.

A metal sphere has 6.0μC and another identical one has 14.0μC on it. The charge on each after being brought into contact is :

1.875 X 10^12

A polythene piece rubbed with wool is found to have a negative charge of 3.2 × 10^-7 C. The number of electrons transferred :_________

+8.9 µC

A positive charge 4.0 µC exerts an attractive force of 8N on an unknown charge 20cm away. The unknown charge is _______.

It moves to the left

A rigid electric dipole is free to move in the electric field represented in the figure. Which one of the following phrases most accurately describes the initial motion of the dipole if it is released from rest in the position shown?

Net force to the left and a counterclockwise rotation Next

A rigid insulated rod, with two unequal charges attached to its ends, is placed in a uniform electric field E as shown above. The rod experiences a ___________.

4.0 x 1017 C

An 8.20 x 10-15kg oil drop is moving upwards at a constant speed of 1.60 m/s between the horizontal plates. If the electric field strength between the plates is 2000 N/C, determine the magnitude of the drops charge.

Up

An electron enters a region which is known to have a uniform electric field. If the electron leaves the region a distance d lower than it entered the region, as shown, which vector represents the electric field in the specified region?

The velocity of the electron will decrease

An electron enters an electric field with its velocity in the direction of the electric field. Then, _______________.

(eE)/m

An electron having charge e and mass m is moving in a uniform electric field E. Its acceleration will be ________.

Downward

An electron traveling horizontally enters a region where a uniform electric field is directed upward. What is the direction of the force exerted on the electron once it has entered the field?

Gaining electrons

An object becomes negatively charged by _______.

2

As the charge of Object A is doubled, the electric field strength created by object A increases by a factor of ____.

Quartered

From the Coulomb's Law, if the distance r between the charges is doubled, the electric force FE becomes ____.

82

How many electrons are there in a lead atom?

Negative charge

If a substance has a higher number of electrons than protons on its surface, what type of charge does it have?

Reduced by 1/4

If the distance between 2 charges doubles, what happens to the electrostatic force?

In opposite direction as the field

In what direction will a negatively charged particle accelerate in an electric field?

The distance between two charges doubles at the same time that the charge on each also doubles. What happens to the electric force?

No Change

Attract

Particles with opposite charges _________ each other.

True

TRUE/FALSE: At a location of 0.200 m from object A, the electric field strength is 0.0500 N/C. If the electric field strength were measured using a test charge with twice the charge at a location of 0.100 m from object A, then the field strength would be 0.200 N/C.

120µC

The electric field has a magnitude of 3.0 N/C at a distance of 60 cm from a point charge. What is the charge?

0

The electrical field inside a perfectly conducting media is _________.

Coulomb's Law

The law, governing the force between electric charges is known as

J/C

The unit of electric field is NOT equivalent to____.

10√2

There is a uniform electric field of strength 103 N/C along the y-axis. A body of mass of 1 g and charge 10-6 is projected into the field from the origin along the positive x-axis with a velocity 10 m/s. After 10s its velocity is _______.

Horizontal - 76 N; Vertical - 370 N

Three point charges are arranged along the x-axis. Charge q1 = +3 C is at the origin, and charge q2 = -5 C is at x = 0.200 m. Charge q3 = -9 C. Where is q3 located if the net force on q1 is 7.00 N in the -x direction in meter?

18.6189

Three point charges are arranged along the x-axis. Charge q1 = +3 uC is at the origin, and charge q2 = -5 uC is at x = 0.200 m. Charge q3 = -9 iC. Where is q3 located if the net force on q1 is 7.00 N in the -x direction in meter?

Smaller

Two charges are initially 1.2 m apart. After an hour, they are 2 m apart. The force between them becomes ____.

The electrons flow to the Earth.

Two identical metal spheres A and B are on their insulator mountings, both initially neutral. A is on the left and B on the right. They are first brought into contact. A negatively charged rod is then held close to the left of A. To answer the following question, drawing a figure is absolutely necessary. If you connect the right of sphere B to the neutral Earth,

-0.00782666N

Two point charges, q1 = +33 nC and q2 = -95 nC, are separated by a distance of 6 cm. Find the magnitude of the force (in N) that q2 exerts on q1.

-0.0089

Two point charges, q1 = +40 nC and q2 = -89 nC, are separated by a distance of 6 cm. Find the magnitude of the force (in N) that q2 exerts on q1. Numerical Answer only. Round off to four (4) decimal places.

A Positive : B Negative

Two uncharged, conducting spheres, A and B, are held at rest on insulating stands and are in contact. A positively charged rod is brought near sphere A as suggested in the figure. While the rod is in place, someone moves sphere B away from A. How will the spheres be charged, if at all?

Electron

What atomic particles move from one surface to another in order to form a static charge?

9 times less electric force

What happens to the electric force between two charges when the distance is tripled?

3.370

What is the magnitude of the electric field in N/C at a field point 4 m from a point charge q = 6 nC?

1.7476

What is the magnitude of the electric field in N/C at a field point 6 m from a point charge q = 7 nC?

1.284

What is the magnitude of the electric field in N/C at a field point 7 m from a point charge q = 7 nC?

0

What is the overall charge of a carbon atom?

A lightning strike during a storm

Which of the following is caused by static electricity?

It is a measure of the electric force per unit charge on a test charge.

Which one of the following statements is true concerning the magnitude of the electric field at a point in space?

I and III

With electric field lines, how are stronger electric fields represented? I. By electric field lines that are close together II. By electric field lines that are far apart III. By using long vector arrows IV. By using short vector arrows