Question 1

The electric field in a region is given by  where the units are in V/m. What is the potential from the origin to (x, y) = (2, 2) m?

Accepted Answer

A

Question 2

A uniform electric field exists between two parallel plates separated by 1.2 cm. The intensity of the field is 23 kN/C. What is the potential difference between the plates?

Accepted Answer

E

Question 3

Charges Q and q (Q $\neq$ q), separated by a distance d, produce a potential V_P = 0 at point P. This means that

Accepted Answer

E

Question 4

The concept of difference in electric potential is most closely associated with

Accepted Answer

Difference in electric potential is a measure of the work per unit quantity of electricity required to move a charge between two points.

Question 5

Two parallel metal plates 5.0 cm apart have a potential difference between them of 75 V. The electric force on a positive charge of 3.2 × 10^-¹⁹ C at a point midway between the plates is approximately

Accepted Answer

The answer of Two parallel metal plates 5.0 cm apart...

Question 6

When 5.0 C of charge moves at constant speed along a path between two points differing in potential by 12 V, the amount of work done is

Accepted Answer

The answer of When 5.0 C of charge moves at...

Question 7

The voltage between the cathode and the screen of a computer monitor is 12 kV. If we assume a speed of zero for an electron as it leaves the cathode, what is its speed just before it hits the screen?

Accepted Answer

Using conservation of energy, we can find the electron's final velocity:
$$\frac{1}{2}mv^2=qV$$
where $m$ is the mass of an electron, $q$ is the charge of an electron, and $V$ is the potential difference between the cathode and screen.
Solving for $v$:
$$v=\sqrt{\frac{2qV}{m}}=\sqrt{\frac{2(1.602	imes10^{-19}	ext{ C})(12	imes10^3	ext{ V})}{9.109	imes10^{-31}	ext{ kg}}}$$
$$v=6.5	imes10^7 	ext{ m/s}$$
rounded to 2 significant figures. Therefore, the answer is B.

Question 8

The electric field in a region is given by  where the units are in V/m. What is the potential from the origin to (x, y) = (2, 0) m?

Accepted Answer

To find the potential, we need to integrate the electric field:
V = -∫E•ds, where s is the path from the origin to (2,0).
Let's choose a straight line path along the x-axis, so ds = dx and we have:
V = -∫E•ds = -∫11x dx = -[11x^2/2]_0^2 = -22/2 = -11 V
Note that we have to put a negative sign because the electric field points in the positive x-direction and we are moving in the negative x-direction to get from the origin to (2,0).
Therefore, the answer is C) -16/3 V, which is the potential difference between the origin and (2,0).

Question 9

A lithium nucleus with a charge of 3(1.6 × 10^-¹⁹) C and a mass of 7(1.67 × 10^-²⁷) kg, and an alpha particle with a charge of 2(1.6 × 10^-¹⁹) C and a mass of 4(1.67 × 10^-²⁷) kg, are at rest. They could be accelerated to the same kinetic energy by

Accepted Answer

The kinetic energy of a moving particle can be found using the equation KE = (1/2)mv^2, where KE is the kinetic energy, m is the mass of the particle, and v is its velocity. Since both particles are at rest initially, their initial kinetic energies are zero. Therefore, the final kinetic energy for both particles is the same, regardless of their charges or masses. 
To give both particles the same kinetic energy, we need to accelerate them to the same velocity. The velocity of a charged particle that has been accelerated through an electrical potential difference V can be found using the equation v = (2qV/m)^0.5, where q is the charge of the particle and m is its mass. 
For the lithium nucleus: 
v = (2 * 3 * 1.6 × 10^-19 C * V / 7 * 1.67 × 10^-27 kg)^0.5 
v = (9.6 × 10^8 V / 1.17 × 10^-26 kg)^0.5 
v ≈ 7.04 × 10^5 m/s 
For the alpha particle: 
v = (2 * 2 * 1.6 × 10^-19 C * V / 4 * 1.67 × 10^-27 kg)^0.5 
v = (6.4 × 10^8 V / 6.68 × 10^-27 kg)^0.5 
v ≈ 9.31 × 10^5 m/s 
We need to find a value of V such that both particles reach the same velocity: 
7.04 × 10^5 m/s = 9.31 × 10^5 m/s 
(2 * 3 * 1.6 × 10^-19 C * V / 7 * 1.67 × 10^-27 kg)^0.5 = (2 * 2 * 1.6 × 10^-19 C * V / 4 * 1.67 × 10^-27 kg)^0.5 
(3 * V / 7)^0.5 = (V / 2)^0.5 
V = (2/3)^2 * (7/3) * (1.6 × 10^-19 C / 1.67 × 10^-27 kg) 
V ≈ 4.63 × 10^7 V 
Therefore, we need to accelerate the alpha particle through V volts and the lithium nucleus through 2V/3 volts, which corresponds to choice B.

Question 10

A charge of 2.0 mC is located in a uniform electric field of intensity 4.0 × 10⁵ N/C. How much work is required to move this charge 20 cm along a path making an angle of 60° with the electric field?

Accepted Answer

The answer of A charge of 2.0 mC is located...

Question 11

The electron volt is a unit of

Accepted Answer

The electron volt is a unit of energy, specifically the amount of energy gained or lost by an electron moving across an electric potential difference of one volt.

Question 12

Two parallel horizontal plates are spaced 0.40 cm apart in air. You introduce an oil droplet of mass 4.9 × 10^-¹⁷ kg between the plates. If the droplet carries two electronic charges and if there were no air buoyancy, you could hold the droplet motionless between the plates if you kept the potential difference between them at

Accepted Answer

The answer of Two parallel horizontal plates are spaced 0.40...

Question 13

When 2.0 C of charge moves at constant speed along a path between two points differing in potential by 6.0 V, the amount of work done is

Accepted Answer

The work done is calculated using the formula W = QV, where W is work, Q is charge, and V is potential difference. Substituting the given values, W = 2.0 C * 6.0 V = 12 J.

Question 14

Correct units for electric potential are

Accepted Answer

Electric potential is measured in volts, which is equivalent to joules per coulomb (J/C). This unit represents the work done per unit charge.

Question 15

A uniform electric field exists between two parallel plates separated by 2.0 cm. The intensity of the field is 15 kN/C. What is the potential difference between the plates?

Accepted Answer

The answer of A uniform electric field exists between two...

Question 16

The voltage between the cathode and the screen of a television set is 22 kV. If we assume a speed of zero for an electron as it leaves the cathode, what is its speed just before it hits the screen?

Accepted Answer

The answer of The voltage between the cathode and the...

Question 17

Two parallel metal plates 0.35 cm apart have a potential difference between them of 175 V. The electric force on a positive charge of 6.4 × 10^-¹⁹ C at a point midway between the plates is approximately

Accepted Answer

The answer of Two parallel metal plates 0.35 cm apart...

Question 18

Two parallel horizontal plates are spaced 0.60 cm apart in air. You introduce an oil droplet of mass 7.4 × 10^-¹⁷ kg between the plates. If the droplet carries five electronic charges and if there were no air buoyancy, you could hold the droplet motionless between the plates if you kept the potential difference between them at

Accepted Answer

The answer of Two parallel horizontal plates are spaced 0.60...

Question 19

The electric field in a region is given by  where Q is the charge. What is the potential between r = a to r = b?

Accepted Answer

The answer of The electric field in a region is...

Question 20

A charge of 5.0 mC is located in a uniform electric field of intensity 3.5 × 10⁵ N/C. How much work is required to move this charge 50 cm along a path making an angle of 33° with the electric field?

Accepted Answer

The answer of A charge of 5.0 mC is located...

Quiz 3: Electric Potential

The electric field in a region is given by where the units are in V/m. What is the potential from the origin to (x, y) = (2, 2) m?

A uniform electric field exists between two parallel plates separated by 1.2 cm. The intensity of the field is 23 kN/C. What is the potential difference between the plates?

Charges Q and q (Q ≠\neq= q) , separated by a distance d, produce a potential VP = 0 at point P. This means that

The concept of difference in electric potential is most closely associated with

Two parallel metal plates 5.0 cm apart have a potential difference between them of 75 V. The electric force on a positive charge of 3.2 × 10-19 C at a point midway between the plates is approximately

When 5.0 C of charge moves at constant speed along a path between two points differing in potential by 12 V, the amount of work done is

The voltage between the cathode and the screen of a computer monitor is 12 kV. If we assume a speed of zero for an electron as it leaves the cathode, what is its speed just before it hits the screen?

The electric field in a region is given by where the units are in V/m. What is the potential from the origin to (x, y) = (2, 0) m?

A lithium nucleus with a charge of 3(1.6 × 10-19) C and a mass of 7(1.67 × 10-27) kg, and an alpha particle with a charge of 2(1.6 × 10-19) C and a mass of 4(1.67 × 10-27) kg, are at rest. They could be accelerated to the same kinetic energy by

A charge of 2.0 mC is located in a uniform electric field of intensity 4.0 × 105 N/C. How much work is required to move this charge 20 cm along a path making an angle of 60° with the electric field?