Question 1

If a = 3.0 mm,b = 4.0 mm,Q1 = 60 nC,Q2 = 80 nC,and q = 32 nC in the figure,what is the magnitude of the electric force on q?

Accepted Answer

A) 1.6 N 
B) 1.3 N 
C) 1.9 N 
D) 2.2 N 
E) 0.040 N 
A) 1.6 N 
B) 1.3 N 
C) 1.9 N 
D) 2.2 N 
E) 0.040 N

Question 2

If we define the gravitational field $\overrightarrow { \mathbf { g } } = \frac { - G M _ { \text {source } } } { r ^ { 2 } } \hat { \mathbf { r } }$ ,where $\hat{r}$ is a unit radial vector,then Gauss's Law for gravity is

Accepted Answer

A)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - G M _ { \text {source } }$ . 
B)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = + G M _ { \text {source } }$ . 
C)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - 4 \pi G M _ { \text {source } }$ . 
D)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = + 4 \pi G M _ { \text {source } }$ . 
E)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - 4 \pi G M _ { \text {source } } m _ { \text {object } }$ . 
A)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - G M _ { \text {source } }$ . 
B)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = + G M _ { \text {source } }$ . 
C)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - 4 \pi G M _ { \text {source } }$ . 
D)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = + 4 \pi G M _ { \text {source } }$ . 
E)  $\oint \overrightarrow { \mathbf { g } } \cdot d \mathbf { A } = - 4 \pi G M _ { \text {source } } m _ { \text {object } }$ .

Question 3

Charge of uniform density (40 pC/m2)is distributed on a spherical surface (radius = 1.0 cm),and a second concentric spherical surface (radius = 3.0 cm)carries a uniform charge density of 60 pC/m2.What is the magnitude of the electric field at a point 2.0 cm from the center of the two surfaces?

Accepted Answer

A) 1.1 N/C 
B) 4.5 N/C 
C) 1.4 N/C 
D) 5.6 N/C 
E) 0.50 N/C 
A) 1.1 N/C 
B) 4.5 N/C 
C) 1.4 N/C 
D) 5.6 N/C 
E) 0.50 N/C

Question 4

A student has made the statement that the electric flux through one half of a Gaussian surface is always equal and opposite to the flux through the other half of the Gaussian surface.This is

Accepted Answer

A) never true. 
B) never false. 
C) true whenever enclosed charge is symmetrically located at a center point,or on a center line or centrally placed plane. 
D) true whenever no charge is enclosed within the Gaussian surface. 
E) true only when no charge is enclosed within the Gaussian surface. 
A) never true. 
B) never false. 
C) true whenever enclosed charge is symmetrically located at a center point,or on a center line or centrally placed plane. 
D) true whenever no charge is enclosed within the Gaussian surface. 
E) true only when no charge is enclosed within the Gaussian surface.

Question 5

Rubber rods charged by rubbing with cat fur repel each other.Glass rods charged by rubbing with silk repel each other.A rubber rod and a glass rod charged respectively as above attract each other.A possible explanation is that

Accepted Answer

A) Any two rubber rods charged this way have opposite charges on them. 
B) Any two glass rods charged this way have opposite charges on them. 
C) A rubber rod and a glass rod charged this way have opposite charges on them. 
D) All rubber rods always have an excess of positive charge on them. 
E) All glass rods always have an excess of negative charge on them. 
A) Any two rubber rods charged this way have opposite charges on them. 
B) Any two glass rods charged this way have opposite charges on them. 
C) A rubber rod and a glass rod charged this way have opposite charges on them. 
D) All rubber rods always have an excess of positive charge on them. 
E) All glass rods always have an excess of negative charge on them.

Question 6

If a = 60 cm,b = 80 cm,Q = -6.0 nC,and q = 6.0 nC,what is the magnitude of the electric field at point P in the figure?

Accepted Answer

A) 65 N/C 
B) 55 N/C 
C) 60 N/C 
D) 52 N/C 
E) 67 N/C 
A) 65 N/C 
B) 55 N/C 
C) 60 N/C 
D) 52 N/C 
E) 67 N/C

Question 7

A uniformly charged rod (length = 2.0 m,charge per unit length = 3.0 nC/m)is bent to form a semicircle.What is the magnitude of the electric field at the center of the circle?

Accepted Answer

A) 64 N/C 
B) 133 N/C 
C) 48 N/C 
D) 85 N/C 
E) 34 N/C 
A) 64 N/C 
B) 133 N/C 
C) 48 N/C 
D) 85 N/C 
E) 34 N/C

Question 8

A student has made the statement that the electric flux through one half of a Gaussian surface is always equal to the flux through the other half of the Gaussian surface.This is

Accepted Answer

A) never true. 
B) never false. 
C) true whenever enclosed charge is symmetrically located at a center point,on a center line,or on a centrally placed plane. 
D) true whenever no charge is enclosed within the Gaussian surface. 
E) true only when no charge is enclosed within the Gaussian surface. 
A) never true. 
B) never false. 
C) true whenever enclosed charge is symmetrically located at a center point,on a center line,or on a centrally placed plane. 
D) true whenever no charge is enclosed within the Gaussian surface. 
E) true only when no charge is enclosed within the Gaussian surface.

Question 9

Two uniform rods,each of length 2.0 m,are bent to form semicircles.One rod has a charger per unit lent of 1.5 nC/m,and the other has a charge per unit length of -1.5 nC/m.The semicircles are joined to make a circle.What is the magnitude of the electric field at the center of the circle?

Accepted Answer

A) 42 N/C 
B) 84 N/C 
C) 34 N/C 
D) 68 N/C 
E) 0 
A) 42 N/C 
B) 84 N/C 
C) 34 N/C 
D) 68 N/C 
E) 0

Question 10

Charge of uniform surface density (4.0 nC/m2)is distributed on a spherical surface (radius = 2.0 cm).What is the total electric flux through a concentric spherical surface with a radius of 4.0 cm?

Accepted Answer

A) 2.8 N.m2/C 
B) 1.7 N. m2/C 
C) 2.3 N. m2/C 
D) 4.0 N . m2/C 
E) 9.1 N. m2/C 
A) 2.8 N.m2/C 
B) 1.7 N. m2/C 
C) 2.3 N. m2/C 
D) 4.0 N . m2/C 
E) 9.1 N. m2/C

Question 11

A uniform linear charge density of 4.0 nC/m is distributed along the entire x axis.Consider a spherical (radius = 5.0 cm)surface centered on the origin.Determine the electric flux through this surface.

Accepted Answer

A) 68 N . m2/C 
B) 62 N . m2/C 
C) 45 N . m2/C 
D) 79 N . m2/C 
E) 23 N. m2/C 
A) 68 N . m2/C 
B) 62 N . m2/C 
C) 45 N . m2/C 
D) 79 N . m2/C 
E) 23 N. m2/C

Question 12

If a = 3.0 mm,b = 4.0 mm,Q1 = -60 nC,Q2 = 80 nC,and q = 30 nC in the figure,what is the magnitude of the electric force on q?

Accepted Answer

A) 1.4 N 
B) 1.0 N 
C) 1.7 N 
D) 2.0 N 
E) 0.50 N 
A) 1.4 N 
B) 1.0 N 
C) 1.7 N 
D) 2.0 N 
E) 0.50 N

Question 13

The nucleus of a hydrogen atom,a proton,sets up an electric field.The distance between the proton and electron is about 5.1 * 10 - 11 m.What is the magnitude of the electric field at this distance from the proton? [The charge on the proton is +1.6 *10 - 19 C.]

Accepted Answer

5.5 * 10<s

Question 14

A 5.0-nC point charge is embedded at the center of a nonconducting sphere (radius = 2.0 cm)which has a charge of -8.0 nC distributed uniformly throughout its volume.What is the magnitude of the electric field at a point that is 1.0 cm from the center of the sphere?

Accepted Answer

A) 1.8* 105 N/C 
B) 9.0 * 104 N/C 
C) 3.6*105 N/C 
D) 2.7 * 105 N/C 
E) 7.2 * 105 N/C 
A) 1.8* 105 N/C 
B) 9.0 * 104 N/C 
C) 3.6*105 N/C 
D) 2.7 * 105 N/C 
E) 7.2 * 105 N/C

Question 15

A long nonconducting cylinder (radius = 6.0 mm)has a nonuniform volume charge density given by $\alpha$r2,where $\alpha$ = 6.2 mC/m5 and r is the distance from the axis of the cylinder.What is the magnitude of the electric field at a point 2.0 mm from the axis?

Accepted Answer

A) 1.4 N/C 
B) 1.6 N/C 
C) 1.8 N/C 
D) 2.0 N/C 
E) 5.4 N/C 
A) 1.4 N/C 
B) 1.6 N/C 
C) 1.8 N/C 
D) 2.0 N/C 
E) 5.4 N/C

Question 16

An astronaut is in an all-metal chamber outside the space station when a solar storm results in the deposit of a large positive charge on the station.Which statement is correct?

Accepted Answer

A) The astronaut must abandon the chamber immediately to avoid being electrocuted. 
B) The astronaut will be safe only if she is wearing a spacesuit made of non-conducting materials. 
C) The astronaut does not need to worry: the charge will remain on the outside surface. 
D) The astronaut must abandon the chamber if the electric field on the outside surface becomes greater than the breakdown field of air. 
E) The astronaut must abandon the chamber immediately because the electric field inside the chamber is non-uniform. 
A) The astronaut must abandon the chamber immediately to avoid being electrocuted. 
B) The astronaut will be safe only if she is wearing a spacesuit made of non-conducting materials. 
C) The astronaut does not need to worry: the charge will remain on the outside surface. 
D) The astronaut must abandon the chamber if the electric field on the outside surface becomes greater than the breakdown field of air. 
E) The astronaut must abandon the chamber immediately because the electric field inside the chamber is non-uniform.

Question 17

Which one of the diagrams below is not a possible electric field configuration for a region of space which does not contain any charges?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 18

Three 2.50 $\mu$C charges are placed on tiny conducting spheres at the ends of 1.00 m-long strings that are connected at 120$\degree$ angles as shown below.The magnitude,in N,of the force on any one of the charges is

Accepted Answer

A) 1.88 * 10 - 2. 
B) 3.25 * 10 - 2. 
C) 3.73 *10 - 2. 
D) 6.50 *10 - 2. 
E) 7.50 * 10 - 2. 
A) 1.88 * 10 - 2. 
B) 3.25 * 10 - 2. 
C) 3.73 *10 - 2. 
D) 6.50 *10 - 2. 
E) 7.50 * 10 - 2.

Question 19

At the point of fission,a nucleus of U-238,with 92 protons is divided into two smaller spheres each with 46 protons and a radius of 5.9 *10 - 15 m.What is the repulsive force pushing the two spheres apart when they are just touching one another? (The mass of the U-238 nucleus is 3.98 *10 - 25 kg. )

Accepted Answer

The answer of At the point of fission,a nucleus of...

Question 20

The field just outside the surface of a long conducting cylinder which has a 2.0-cm radius points radially outward and has a magnitude of 200 N/C.What is the charge density on the surface of the cylinder?

Accepted Answer

A) 2.7 nC/m2 
B) 1.8 nC/m2 
C) 3.5 nC/m2 
D) 4.4 nC/m2 
E) 0.90 nC/m2 
A) 2.7 nC/m2 
B) 1.8 nC/m2 
C) 3.5 nC/m2 
D) 4.4 nC/m2 
E) 0.90 nC/m2

Exam 19: Electric Forces and Electric Fields

If a = 3.0 mm,b = 4.0 mm,Q1 = 60 nC,Q2 = 80 nC,and q = 32 nC in the figure,what is the magnitude of the electric force on q?

If we define the gravitational field g→=−GMsource r2r^\overrightarrow { \mathbf { g } } = \frac { - G M _ { \text {source } } } { r ^ { 2 } } \hat { \mathbf { r } }g​=r2−GMsource ​​r^ ,where r^\hat{r}r^ is a unit radial vector,then Gauss's Law for gravity is

Charge of uniform density (40 pC/m2)is distributed on a spherical surface (radius = 1.0 cm),and a second concentric spherical surface (radius = 3.0 cm)carries a uniform charge density of 60 pC/m2.What is the magnitude of the electric field at a point 2.0 cm from the center of the two surfaces?

A student has made the statement that the electric flux through one half of a Gaussian surface is always equal and opposite to the flux through the other half of the Gaussian surface.This is

Rubber rods charged by rubbing with cat fur repel each other.Glass rods charged by rubbing with silk repel each other.A rubber rod and a glass rod charged respectively as above attract each other.A possible explanation is that

If a = 60 cm,b = 80 cm,Q = -6.0 nC,and q = 6.0 nC,what is the magnitude of the electric field at point P in the figure?

A uniformly charged rod (length = 2.0 m,charge per unit length = 3.0 nC/m)is bent to form a semicircle.What is the magnitude of the electric field at the center of the circle?

A student has made the statement that the electric flux through one half of a Gaussian surface is always equal to the flux through the other half of the Gaussian surface.This is

Two uniform rods,each of length 2.0 m,are bent to form semicircles.One rod has a charger per unit lent of 1.5 nC/m,and the other has a charge per unit length of -1.5 nC/m.The semicircles are joined to make a circle.What is the magnitude of the electric field at the center of the circle?

Charge of uniform surface density (4.0 nC/m2)is distributed on a spherical surface (radius = 2.0 cm).What is the total electric flux through a concentric spherical surface with a radius of 4.0 cm?

A uniform linear charge density of 4.0 nC/m is distributed along the entire x axis.Consider a spherical (radius = 5.0 cm)surface centered on the origin.Determine the electric flux through this surface.

If a = 3.0 mm,b = 4.0 mm,Q1 = -60 nC,Q2 = 80 nC,and q = 30 nC in the figure,what is the magnitude of the electric force on q?

The nucleus of a hydrogen atom,a proton,sets up an electric field.The distance between the proton and electron is about 5.1 * 10 - 11 m.What is the magnitude of the electric field at this distance from the proton? [The charge on the proton is +1.6 *10 - 19 C.]

A 5.0-nC point charge is embedded at the center of a nonconducting sphere (radius = 2.0 cm)which has a charge of -8.0 nC distributed uniformly throughout its volume.What is the magnitude of the electric field at a point that is 1.0 cm from the center of the sphere?

A long nonconducting cylinder (radius = 6.0 mm)has a nonuniform volume charge density given by α\alphaα r2,where α\alphaα = 6.2 mC/m5 and r is the distance from the axis of the cylinder.What is the magnitude of the electric field at a point 2.0 mm from the axis?

An astronaut is in an all-metal chamber outside the space station when a solar storm results in the deposit of a large positive charge on the station.Which statement is correct?

Which one of the diagrams below is not a possible electric field configuration for a region of space which does not contain any charges?

Three 2.50 μ\muμ C charges are placed on tiny conducting spheres at the ends of 1.00 m-long strings that are connected at 120 °\degree° angles as shown below.The magnitude,in N,of the force on any one of the charges is

At the point of fission,a nucleus of U-238,with 92 protons is divided into two smaller spheres each with 46 protons and a radius of 5.9 *10 - 15 m.What is the repulsive force pushing the two spheres apart when they are just touching one another? (The mass of the U-238 nucleus is 3.98 *10 - 25 kg. )

The field just outside the surface of a long conducting cylinder which has a 2.0-cm radius points radially outward and has a magnitude of 200 N/C.What is the charge density on the surface of the cylinder?

Introduction and Vectors

Motion in One Dimension

Motion in Two Dimensions

The Laws of Motion

More Applications of Newtons Laws

Energy of a System

Conservation of Energy

Momentum and Collisions

Relativity

Rotational Motion

Gravity,planetary Orbits,and the Hydrogen Atom

Oscillatory Motion

Mechanical Waves

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Fluid Mechanics

Temperature and the Kinetic Theory of Gases

Energy in Thermal Processes: the First Law of Thermodynamics

Heat Engines,entropy,and the Second Law of Thermodynamics

Electric Potential and Capacitance

Current and Direct Current Circuits

Magnetic Forces and Magnetic Fields

Faradays Law and Inductance

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Filters

If a = 3.0 mm,b = 4.0 mm,Q₁ = 60 nC,Q₂ = 80 nC,and q = 32 nC in the figure,what is the magnitude of the electric force on q?

If we define the gravitational field $\overrightarrow { \mathbf { g } } = \frac { - G M _ { \text {source } } } { r ^ { 2 } } \hat { \mathbf { r } }$ ,where $\hat{r}$ is a unit radial vector,then Gauss's Law for gravity is

Charge of uniform density (40 pC/m²)is distributed on a spherical surface (radius = 1.0 cm),and a second concentric spherical surface (radius = 3.0 cm)carries a uniform charge density of 60 pC/m².What is the magnitude of the electric field at a point 2.0 cm from the center of the two surfaces?

Charge of uniform surface density (4.0 nC/m²)is distributed on a spherical surface (radius = 2.0 cm).What is the total electric flux through a concentric spherical surface with a radius of 4.0 cm?

If a = 3.0 mm,b = 4.0 mm,Q₁ = -60 nC,Q₂ = 80 nC,and q = 30 nC in the figure,what is the magnitude of the electric force on q?

The nucleus of a hydrogen atom,a proton,sets up an electric field.The distance between the proton and electron is about 5.1 * 10 ^- ¹¹ m.What is the magnitude of the electric field at this distance from the proton? [The charge on the proton is +1.6 *10 ^- ¹⁹ C.]

A long nonconducting cylinder (radius = 6.0 mm)has a nonuniform volume charge density given by $\alpha$ r²,where $\alpha$ = 6.2 mC/m⁵ and r is the distance from the axis of the cylinder.What is the magnitude of the electric field at a point 2.0 mm from the axis?