Question 1

A 24.0 kg sample of ice is at 0.00°C. How much heat is needed to melt it? (For water L_f = 334 kJ/kg and L_v = 2257 kJ/kg.)

Accepted Answer

The heat needed to melt the ice is calculated using the formula Q = m * Lf, where m is the mass and Lf is the latent heat of fusion. For 24.0 kg of ice, Q = 24.0 kg * 334 kJ/kg = 8,016 kJ, which is approximately 8.02 × 10^3 kJ.

Question 2

Which of the following is a true statement?

Accepted Answer

A bridge can be icier than the road because it is exposed to cold air on both its top and bottom surfaces, allowing it to lose heat more quickly than the road, which is only exposed on the top.

Question 3

In years of heavy snow pack in the mountains it is sometimes desirable to induce early melting of the snow, rather than wait until it all melts suddenly and causes floods. It has been suggested that a way to accomplish this might be to have planes fly over the snow fields and sprinkle them with black soot. What do you think of this idea? Would it work?

Accepted Answer

Sprinkling black soot on the snow would increase the absorption of sunlight due to the soot's darker color, leading to faster melting of the snow.

Question 4

At higher altitudes it takes __________ time to bring water to a boil on a stove.

Accepted Answer

The answer of At higher altitudes it takes __________ time...

Question 5

You blow on food to cool it. Blowing increases

Accepted Answer

Blowing on food increases convection by moving the warm air away from the surface of the food and replacing it with cooler air, which helps to cool the food down faster.

Question 6

Which of the following relationships are true for all types of heat engines? (There may be more than one correct choice.)

Accepted Answer

The answer of Which of the following relationships are true...

Question 7

A gas is confined to a rigid container that cannot expand as heat energy is added to it. This process is

Accepted Answer

In an isometric process, the volume remains constant. Since the container is rigid and cannot expand, the volume does not change, making the process isometric (also known as isochoric).

Question 8

An ideal gas is compressed to one-half its original volume during an isothermal process. The final pressure of the gas

Accepted Answer

In an isothermal process, the temperature remains constant. According to Boyle's Law (P1V1 = P2V2), if the volume is halved, the pressure must double to maintain the same temperature.

Question 9

As a system loses its ability to do useful work

Accepted Answer

As a system loses its ability to do useful work, its entropy increases, reflecting a higher degree of disorder and less available energy for work.

Question 10

A proton is located at x = 1.0 nm, y = 0.0 nm and an electron is located at x = 0.0 nm, Y = 4.0 nm. Find the attractive Coulombic force between them. (The value of k is 9)0 × 10⁹ N · m²/C².)

Accepted Answer

The attractive Coulombic force between a proton and an electron is given by:$$F = k\frac{e^2}{r^2}$$where:* k is the Coulomb constant (9 × 10^9 N · m^2/C^2)* e is the elementary charge (1.6 × 10^-19 C)* r is the distance between the proton and the electronIn this problem, the distance between the proton and the electron is:$$r = \sqrt{(1.0 	ext{ nm})^2 + (4.0 	ext{ nm})^2} = 4.12 	ext{ nm} = 4.12 	imes 10^{-9} 	ext{ m}$$Substituting these values into the equation for the Coulombic force, we get:$$F = (9 	imes 10^9 	ext{ N} \cdot 	ext{m}^2/	ext{C}^2)\frac{(1.6 	imes 10^{-19} 	ext{ C})^2}{(4.12 	imes 10^{-9} 	ext{ m})^2} = 1.4 	imes 10^{-11} 	ext{ N}$$Therefore, the attractive Coulombic force between the proton and the electron is 1.4 × 10^-11 N.

Question 11

Three charges of magnitude 3.0 × 10^-4 C each are located at x = 1.0 m, y = 0.0 m, at x = 0.0 m, y = 0.0 m, and at x = -1.0 m, y = 0.0 m. The one in the middle is negative, while the other two are positive. What is the net Coulombic force exerted by them on a negative 3.0 × 10^-⁵ C charge located at x = 0.0 m, y = 2.0 m? (The value of k is 9.0 × 10⁹ N · m²/C².)

Accepted Answer

The forces due to the positive charges at x = 1.0 m and x = -1.0 m are attractive and add up, while the force due to the negative charge at the origin is repulsive. Calculating these forces and summing them gives a net force of 87 N, which is attractive.

Question 12

In the figure Q = 5.8 nC and all other quantities are exact. What is the magnitude of the force on the charge Q?

Accepted Answer

The answer of In the figure Q = 5.8 nC...

Question 13

The charge in the bottom right corner of the figure is Q = -45 nC. What is the magnitude of the force on Q?

Accepted Answer

The answer of The charge in the bottom right corner...

Question 14

The charge at the bottom of the figure is Q = + 17 nC. What is the magnitude of the force  on the charge Q?

Accepted Answer

The answer of The charge at the bottom of the...

Question 15

What is the strength of an electric field that a 0.010 C negative charge experiences 0.90 mm from a 0.20 C positive charge? (The value of K is 9.0 × 10⁹ N · m²/C².)

Accepted Answer

The electric field strength E is calculated using the formula E = K * |q| / r^2. Substituting the given values: E = (9.0 × 10^9 N·m²/C²) * (0.20 C) / (0.0009 m)² = 2.2 × 10^15 N/C.

Question 16

A point charge Q = -400 nC and two unknown point charges, ^q₁ and ^q₂, are placed as shown. The electric field at the origin O, due to charges Q, ^q₁ and ^q_2, is equal to zero. In the figure, the number of excess electrons in charge Q, is closest to:

Accepted Answer

The answer of  A point charge Q = -400...

Question 17

Two point charges, Q₁ = -1.0 ?C and Q₂ = + 3.0 ?C, are placed as shown. In the figure, the number of excess electrons in charge Q₁ is closest to:

Accepted Answer

The answer of Two point charges, Q₁ = -1.0...

Question 18

-A pair of charged conducting plates produces a uniform field of 12,000 N/C, directed to the right, between the plates. The separation of the plates is 40 mm. In the figure, an electron is projected from plate A, directly toward plate B, with an initial velocity of v_o = 2.0 × 10⁷ m/s. The velocity of the electron as it strikes plate B is closest to:

Accepted Answer

The answer of 
-A pair of charged conducting plates produces...

Question 19

A hydrogen nucleus, which has a charge e, is situated to the left of a carbon nucleus, which has a charge 6e. Which statement is true?

Accepted Answer

According to Newton's third law, the forces between two charges are equal in magnitude and opposite in direction. The hydrogen nucleus experiences a force to the left, equal in magnitude to the force on the carbon nucleus.

Question 20

If you rub a balloon on your sweater and then press it to a wall, it will often stick there. Why does this happen?

Accepted Answer

Rubbing the balloon transfers electrons to it, giving it a negative charge. This charge induces a positive charge on the wall's surface, creating an attractive force that holds the balloon to the wall.

Quiz 4: Heat, the Laws of Thermodynamics, Electric Charges, Forces, and Fields

A 24.0 kg sample of ice is at 0.00°C. How much heat is needed to melt it? (For water L_f = 334 kJ/kg and L_v = 2257 kJ/kg.)

Which of the following is a true statement?

At higher altitudes it takes __________ time to bring water to a boil on a stove.

You blow on food to cool it. Blowing increases

Which of the following relationships are true for all types of heat engines? (There may be more than one correct choice.)

A gas is confined to a rigid container that cannot expand as heat energy is added to it. This process is

An ideal gas is compressed to one-half its original volume during an isothermal process. The final pressure of the gas

As a system loses its ability to do useful work

A proton is located at x = 1.0 nm, y = 0.0 nm and an electron is located at x = 0.0 nm, Y = 4.0 nm. Find the attractive Coulombic force between them. (The value of k is 9) 0 × 10⁹ N · m²/C².)

In the figure Q = 5.8 nC and all other quantities are exact. What is the magnitude of the force on the charge Q?

The charge in the bottom right corner of the figure is Q = -45 nC. What is the magnitude of the force on Q?

The charge at the bottom of the figure is Q = + 17 nC. What is the magnitude of the force on the charge Q?

What is the strength of an electric field that a 0.010 C negative charge experiences 0.90 mm from a 0.20 C positive charge? (The value of K is 9.0 × 10⁹ N · m²/C².)

A point charge Q = -400 nC and two unknown point charges, ^q₁ and ^q₂, are placed as shown. The electric field at the origin O, due to charges Q, ^q₁ and ^q_2, is equal to zero. In the figure, the number of excess electrons in charge Q, is closest to:

Two point charges, Q₁ = -1.0 ?C and Q₂ = + 3.0 ?C, are placed as shown. In the figure, the number of excess electrons in charge Q₁ is closest to:

A hydrogen nucleus, which has a charge e, is situated to the left of a carbon nucleus, which has a charge 6e. Which statement is true?

If you rub a balloon on your sweater and then press it to a wall, it will often stick there. Why does this happen?

Quiz 4: Heat, the Laws of Thermodynamics, Electric Charges, Forces, and Fields

A 24.0 kg sample of ice is at 0.00°C. How much heat is needed to melt it? (For water Lf = 334 kJ/kg and Lv = 2257 kJ/kg.)

Which of the following is a true statement?

At higher altitudes it takes __________ time to bring water to a boil on a stove.

You blow on food to cool it. Blowing increases

Which of the following relationships are true for all types of heat engines? (There may be more than one correct choice.)

A gas is confined to a rigid container that cannot expand as heat energy is added to it. This process is

An ideal gas is compressed to one-half its original volume during an isothermal process. The final pressure of the gas

As a system loses its ability to do useful work

A proton is located at x = 1.0 nm, y = 0.0 nm and an electron is located at x = 0.0 nm, Y = 4.0 nm. Find the attractive Coulombic force between them. (The value of k is 9) 0 × 109 N · m2/C2.)

In the figure Q = 5.8 nC and all other quantities are exact. What is the magnitude of the force on the charge Q?

The charge in the bottom right corner of the figure is Q = -45 nC. What is the magnitude of the force on Q?

The charge at the bottom of the figure is Q = + 17 nC. What is the magnitude of the force on the charge Q?

What is the strength of an electric field that a 0.010 C negative charge experiences 0.90 mm from a 0.20 C positive charge? (The value of K is 9.0 × 109 N · m2/C2.)

A point charge Q = -400 nC and two unknown point charges, q1 and q2, are placed as shown. The electric field at the origin O, due to charges Q, q1 and q2, is equal to zero. In the figure, the number of excess electrons in charge Q, is closest to:

Two point charges, Q1 = -1.0 ?C and Q2 = + 3.0 ?C, are placed as shown. In the figure, the number of excess electrons in charge Q1 is closest to:

A hydrogen nucleus, which has a charge e, is situated to the left of a carbon nucleus, which has a charge 6e. Which statement is true?

If you rub a balloon on your sweater and then press it to a wall, it will often stick there. Why does this happen?

A 24.0 kg sample of ice is at 0.00°C. How much heat is needed to melt it? (For water L_f = 334 kJ/kg and L_v = 2257 kJ/kg.)

A proton is located at x = 1.0 nm, y = 0.0 nm and an electron is located at x = 0.0 nm, Y = 4.0 nm. Find the attractive Coulombic force between them. (The value of k is 9) 0 × 10⁹ N · m²/C².)

What is the strength of an electric field that a 0.010 C negative charge experiences 0.90 mm from a 0.20 C positive charge? (The value of K is 9.0 × 10⁹ N · m²/C².)

A point charge Q = -400 nC and two unknown point charges, ^q₁ and ^q₂, are placed as shown. The electric field at the origin O, due to charges Q, ^q₁ and ^q_2, is equal to zero. In the figure, the number of excess electrons in charge Q, is closest to:

Two point charges, Q₁ = -1.0 ?C and Q₂ = + 3.0 ?C, are placed as shown. In the figure, the number of excess electrons in charge Q₁ is closest to: