Question 1

In x-ray machines,electrons are subjected to electric fields as great as 4.0 × 105 N/C.Find an electron's acceleration in this field.(me = 9.11 × 10−31 kg,e = 1.6 × 10−19 C)

Accepted Answer

A)  1.1 × 1017 m/s2 
B)  7.0 × 1016 m/s2 
C)  3.6 × 108 m/s2 
D)  4.6 × 1010 m/s2

Question 2

Two point charges,separated by 15 cm,have charge values of +2.0 µC and −4.0 µC,respectively.What is the value of the mutual force between them? (ke = 8.99 × 109 N⋅m2/C2)

Accepted Answer

A)  8.0 × 10−12 N 
B)  3.6 × 10−8 N 
C)  320 N 
D)  3.2 N

Question 3

Electrons in a particle beam each have a kinetic energy of 3.2 × 10−17 J.What is the magnitude of the electric field that will stop these electrons in a distance of 0.05 m? (e = 1.6 × 10−19 C)

Accepted Answer

A)  2000 N/C 
B)  4000 N/C 
C)  200 N/C 
D)  1000 N/C

Question 4

If a negative charge is placed inside a hollow isolated conductor that is originally neutral and the charge does not touch that conductor at any time:

Accepted Answer

A)  both the inner and outer surfaces will become negative. 
B)  both the inner and outer surfaces will remain neutral. 
C)  the outside surface of the conductor will become positively charged. 
D)  the inside surface of the conductor will become positively charged.

Question 5

A metallic object holds a charge of −2.9 × 10−5 C.What total number of electrons does this represent? (e = 1.6 × 10−19 C is the magnitude of the electronic charge. )

Accepted Answer

A)  1.8 × 1014 
B)  2.4 × 1013 
C)  6.1 × 1013 
D)  4.2 × 1014

Question 6

An electron with a charge value of 1.6 × 10−19 C is moving in the presence of an electric field of 300 N/C.What force does the electron experience?

Accepted Answer

A)  2.3 × 10−22 N 
B)  4.8 × 10−17 N 
C)  6.4 × 10−17 N 
D)  1.9 × 10−21 N

Question 7

If the size of the charge value is tripled for one of two point charges maintained at a constant separation,the mutual force between them will be changed by what factor?

Accepted Answer

A)  3.0 
B)  1/9 
C)  9.0 
D)  0.33

Question 8

An electron with a speed of 2.0 × 106 m/s moves into a uniform electric field of 325 N/C that is parallel to the electron's motion.How long does it take to bring the electron to rest? (me = 9.11 × 10−31 kg,e = 1.6 × 10−19 C)

Accepted Answer

A)  3.5 × 10−8 s 
B)  2.3 × 10−6 s 
C)  2.3 × 10−8 s 
D)  1.2 × 10−7 s

Question 9

Two point charges each have a value of 30.0 mC and are separated by a distance of 3.00 cm.What is the electric field midway between the two charges? (ke = 8.99 × 109 N·m2/C2)

Accepted Answer

A)  40.5 × 107 N/C 
B)  20.3 × 107 N/C 
C)  zero 
D)  10.1 × 107 N/C

Question 10

We have a hollow metallic sphere with charge +5.0 µC and radius 5.0 cm.We insert a −10 µC charge at the center of the sphere through a hole in the surface.What charge now rests on the outer surface of the sphere?

Accepted Answer

A)  +10 µC 
B)  +5 µC 
C)  −5 µC 
D)  +15 µC

Question 11

Two point charges,one q and the other -q,form a dipole separated by a distance 2L.A third charge Q is placed midway between these two charges.If the only charge that is negative is -q,what is the force on Q?

Accepted Answer

A) 
 toward -q 
B) 
 toward q 
C) 
 toward -​q 
D) 
 toward q

Question 12

A conducting spherical shell of inner radius r1 and outer radius r2 has a charge Q on it.An additional charge,also Q,is then added to the sphere.What is the resulting charge per unit area on the outer surface of the sphere?

Accepted Answer

A) 
 
B)  No answer given is correct. 
C) 
 
D)

Question 13

Two point charges are separated by 10.0 cm and have charges of +1.00 µC and −1.00 µC,respectively.What is the electric field at a point midway between the two charges? (ke = 8.99 × 109 N·m2/C2)

Accepted Answer

A)  14.4 × 106 N/C 
B)  zero 
C)  28.8 × 106 N/C 
D)  7.19 × 106 N/C

Question 14

A ping-pong ball covered with a conducting graphite coating has a mass of 2.5 × 10−3 kg and a charge of 4.0 µC.What electric field directed upward will exactly balance the weight of the ball? (g = 9.8 m/s2)

Accepted Answer

A)  6.1 × 103 N/C 
B)  2.0 × 10−7 N/C 
C)  5.1 × 106 N/C 
D)  1.2 × 104 N/C

Question 15

A proton moving at 6.0 × 104 m/s is projected at an angle of 30° above a horizontal plane.If an electric field of 400 N/C is acting down,how long does it take the proton to return to the horizontal plane? (Hint: Ignore gravity.mproton = 1.67 × 10−27 kg,qproton = 1.6 × 10−19 C)

Accepted Answer

A)  7.8 × 10−6 s 
B)  1.6 × 10−6 s 
C)  7.8 × 10−7 s 
D)  3.9 × 10−6 s

Question 16

Two point charges,one ​q and the other -q,form a dipole separated by a distance d.A third charge Q is placed midway between these two charges.If the distance between q and -q is then doubled with the Q staying midway between the other two,what happens to the force on Q?

Accepted Answer

A)  It halves. 
B)  It reduces by a factor of 8. 
C)  It stays the same. 
D)  It quarters.

Question 17

Two point charges are placed along a horizontal axis with the following values and positions: +3.0 µC at x = 0 cm and −6.0 µC at x = 20 cm.At what point along the x axis is the electric field zero?

Accepted Answer

A)  8.0 cm 
B)  −48 cm 
C)  −38 cm 
D)  −69 cm

Exam 17: Current and Resistance Electric Current: Part A

In x-ray machines,electrons are subjected to electric fields as great as 4.0 × 10⁵ N/C.Find an electron's acceleration in this field.(m_e = 9.11 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

Two point charges,separated by 15 cm,have charge values of +2.0 µC and −4.0 µC,respectively.What is the value of the mutual force between them? (k_e = 8.99 × 10⁹ N⋅m²/C²)

Electrons in a particle beam each have a kinetic energy of 3.2 × 10−¹⁷ J.What is the magnitude of the electric field that will stop these electrons in a distance of 0.05 m? (e = 1.6 × 10−¹⁹ C)

If a negative charge is placed inside a hollow isolated conductor that is originally neutral and the charge does not touch that conductor at any time:

A metallic object holds a charge of −2.9 × 10−⁵ C.What total number of electrons does this represent? (e = 1.6 × 10−¹⁹ C is the magnitude of the electronic charge. )

An electron with a charge value of 1.6 × 10−¹⁹ C is moving in the presence of an electric field of 300 N/C.What force does the electron experience?

If the size of the charge value is tripled for one of two point charges maintained at a constant separation,the mutual force between them will be changed by what factor?

An electron with a speed of 2.0 × 10⁶ m/s moves into a uniform electric field of 325 N/C that is parallel to the electron's motion.How long does it take to bring the electron to rest? (me = 9.11 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

Two point charges each have a value of 30.0 mC and are separated by a distance of 3.00 cm.What is the electric field midway between the two charges? (k_e = 8.99 × 10⁹ N·m²/C²)

We have a hollow metallic sphere with charge +5.0 µC and radius 5.0 cm.We insert a −10 µC charge at the center of the sphere through a hole in the surface.What charge now rests on the outer surface of the sphere?

Two point charges,one q and the other -q,form a dipole separated by a distance 2L.A third charge Q is placed midway between these two charges.If the only charge that is negative is -q,what is the force on Q?

A conducting spherical shell of inner radius r₁ and outer radius r₂ has a charge Q on it.An additional charge,also Q,is then added to the sphere.What is the resulting charge per unit area on the outer surface of the sphere?

Two point charges are separated by 10.0 cm and have charges of +1.00 µC and −1.00 µC,respectively.What is the electric field at a point midway between the two charges? (k_e = 8.99 × 10⁹ N·m²/C²)

A ping-pong ball covered with a conducting graphite coating has a mass of 2.5 × 10−³ kg and a charge of 4.0 µC.What electric field directed upward will exactly balance the weight of the ball? (g = 9.8 m/s²)

A proton moving at 6.0 × 10⁴ m/s is projected at an angle of 30° above a horizontal plane.If an electric field of 400 N/C is acting down,how long does it take the proton to return to the horizontal plane? (Hint: Ignore gravity.m_proton = 1.67 × 10−²⁷ kg,q_proton = 1.6 × 10−¹⁹ C)

Two point charges,one q and the other -q,form a dipole separated by a distance d.A third charge Q is placed midway between these two charges.If the distance between q and -q is then doubled with the Q staying midway between the other two,what happens to the force on Q?

Two point charges are placed along a horizontal axis with the following values and positions: +3.0 µC at x = 0 cm and −6.0 µC at x = 20 cm.At what point along the x axis is the electric field zero?

Exam 17: Current and Resistance Electric Current: Part A

In x-ray machines,electrons are subjected to electric fields as great as 4.0 × 105 N/C.Find an electron's acceleration in this field.(me = 9.11 × 10−31 kg,e = 1.6 × 10−19 C)

Two point charges,separated by 15 cm,have charge values of +2.0 µC and −4.0 µC,respectively.What is the value of the mutual force between them? (ke = 8.99 × 109 N⋅m2/C2)

Electrons in a particle beam each have a kinetic energy of 3.2 × 10−17 J.What is the magnitude of the electric field that will stop these electrons in a distance of 0.05 m? (e = 1.6 × 10−19 C)

If a negative charge is placed inside a hollow isolated conductor that is originally neutral and the charge does not touch that conductor at any time:

A metallic object holds a charge of −2.9 × 10−5 C.What total number of electrons does this represent? (e = 1.6 × 10−19 C is the magnitude of the electronic charge. )

An electron with a charge value of 1.6 × 10−19 C is moving in the presence of an electric field of 300 N/C.What force does the electron experience?

If the size of the charge value is tripled for one of two point charges maintained at a constant separation,the mutual force between them will be changed by what factor?

An electron with a speed of 2.0 × 106 m/s moves into a uniform electric field of 325 N/C that is parallel to the electron's motion.How long does it take to bring the electron to rest? (me = 9.11 × 10−31 kg,e = 1.6 × 10−19 C)

Two point charges each have a value of 30.0 mC and are separated by a distance of 3.00 cm.What is the electric field midway between the two charges? (ke = 8.99 × 109 N·m2/C2)

We have a hollow metallic sphere with charge +5.0 µC and radius 5.0 cm.We insert a −10 µC charge at the center of the sphere through a hole in the surface.What charge now rests on the outer surface of the sphere?

Two point charges,one q and the other -q,form a dipole separated by a distance 2L.A third charge Q is placed midway between these two charges.If the only charge that is negative is -q,what is the force on Q?

A conducting spherical shell of inner radius r1 and outer radius r2 has a charge Q on it.An additional charge,also Q,is then added to the sphere.What is the resulting charge per unit area on the outer surface of the sphere?

Two point charges are separated by 10.0 cm and have charges of +1.00 µC and −1.00 µC,respectively.What is the electric field at a point midway between the two charges? (ke = 8.99 × 109 N·m2/C2)

A ping-pong ball covered with a conducting graphite coating has a mass of 2.5 × 10−3 kg and a charge of 4.0 µC.What electric field directed upward will exactly balance the weight of the ball? (g = 9.8 m/s2)

A proton moving at 6.0 × 104 m/s is projected at an angle of 30° above a horizontal plane.If an electric field of 400 N/C is acting down,how long does it take the proton to return to the horizontal plane? (Hint: Ignore gravity.mproton = 1.67 × 10−27 kg,qproton = 1.6 × 10−19 C)

Two point charges,one ​q and the other -q,form a dipole separated by a distance d.A third charge Q is placed midway between these two charges.If the distance between q and -q is then doubled with the Q staying midway between the other two,what happens to the force on Q?

Two point charges are placed along a horizontal axis with the following values and positions: +3.0 µC at x = 0 cm and −6.0 µC at x = 20 cm.At what point along the x axis is the electric field zero?

In x-ray machines,electrons are subjected to electric fields as great as 4.0 × 10⁵ N/C.Find an electron's acceleration in this field.(m_e = 9.11 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

Two point charges,separated by 15 cm,have charge values of +2.0 µC and −4.0 µC,respectively.What is the value of the mutual force between them? (k_e = 8.99 × 10⁹ N⋅m²/C²)

Electrons in a particle beam each have a kinetic energy of 3.2 × 10−¹⁷ J.What is the magnitude of the electric field that will stop these electrons in a distance of 0.05 m? (e = 1.6 × 10−¹⁹ C)

A metallic object holds a charge of −2.9 × 10−⁵ C.What total number of electrons does this represent? (e = 1.6 × 10−¹⁹ C is the magnitude of the electronic charge. )

An electron with a charge value of 1.6 × 10−¹⁹ C is moving in the presence of an electric field of 300 N/C.What force does the electron experience?

An electron with a speed of 2.0 × 10⁶ m/s moves into a uniform electric field of 325 N/C that is parallel to the electron's motion.How long does it take to bring the electron to rest? (me = 9.11 × 10−³¹ kg,e = 1.6 × 10−¹⁹ C)

Two point charges each have a value of 30.0 mC and are separated by a distance of 3.00 cm.What is the electric field midway between the two charges? (k_e = 8.99 × 10⁹ N·m²/C²)

A conducting spherical shell of inner radius r₁ and outer radius r₂ has a charge Q on it.An additional charge,also Q,is then added to the sphere.What is the resulting charge per unit area on the outer surface of the sphere?

Two point charges are separated by 10.0 cm and have charges of +1.00 µC and −1.00 µC,respectively.What is the electric field at a point midway between the two charges? (k_e = 8.99 × 10⁹ N·m²/C²)

A ping-pong ball covered with a conducting graphite coating has a mass of 2.5 × 10−³ kg and a charge of 4.0 µC.What electric field directed upward will exactly balance the weight of the ball? (g = 9.8 m/s²)

A proton moving at 6.0 × 10⁴ m/s is projected at an angle of 30° above a horizontal plane.If an electric field of 400 N/C is acting down,how long does it take the proton to return to the horizontal plane? (Hint: Ignore gravity.m_proton = 1.67 × 10−²⁷ kg,q_proton = 1.6 × 10−¹⁹ C)

Two point charges,one q and the other -q,form a dipole separated by a distance d.A third charge Q is placed midway between these two charges.If the distance between q and -q is then doubled with the Q staying midway between the other two,what happens to the force on Q?