🏷️ LIMITED TIME OFFER: GET 20% OFF GRADE+ YEARLY SUBSCRIPTION →
Log in
Physics
3
answers
1
watching
256
views

Which of the statements is NOT correct? a) When AG for a reaction is negative, the reaction is spontaneous. b) When AG for a reaction is positive, the reaction is nonspontaneous. c) When AG for a reaction is zero, the system is at equilibrium. d) When AH for a reaction is negative, the reaction is never spontaneous. e) When AH for a reaction is very positive, the reaction is not expected to be spontaneous.

2EE02E33-40F2-4165-B43C-6C80B31B950D.jpeg
Watch
3
answers
1
watching
256
views

For unlimited access to Homework Help, a Homework+ subscription is required.

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share
Already have an account? Log in
Share
Already have an account? Log in
Share

Related textbook solutions

Physics: Principles with Applications
7th Edition, 2013
Giancoli
ISBN: 9780321625922

Related questions

<p>A particle vibrates in simple harmonic motion along a vertical line between y1 and y2 as shown in the figure below. y = 0 is the equilibrium position. (Hint: Consider the relationship between acceleration and displacement for a particle in simple harmonic motion. Assume up along the screen is the positive direction.)<br />(a) Which of the following is true when the particle is at the highest point in its oscillation (y1)? (Select all that apply.)<br />1<br />zero velocity maximum negative velocity maximum negative acceleration maximum positive velocity zero acceleration maximum positive acceleration<br /><br /><br />(b) Which of the following is true when the particle is at the equilibrium position (y = 0) and is on its downward journey? (Select all that apply.)<br />2<br />zero velocity maximum negative velocity maximum negative acceleration maximum positive velocity zero acceleration maximum positive acceleration<br /><br /><br />(c) Which of the following is true when the particle is at the lowest point in its oscillation (y2)? (Select all that apply.)<br />3<br />zero velocity maximum negative velocity maximum negative acceleration maximum positive velocity zero acceleration maximum positive acceleration</p>

 

Which statements about potential energy are correct? Select all that apply.
a) The potential energy of a pair of interacting charged objects increases as the distance between them increases.


b) Potential energy can be either positive or negative.


c)When two interacting charged objects get very far away from each other, their potential energy approaches zero.


d) Potential energy is a property of a pair of objects.


e)A single isolated object can have potential energy.


f) A single particle does not have potential energy.


g)Potential energy is always a positive number.

The Sun is powered by nuclear fusion. In each chain reaction, four hydrogen nuclei fuse together to become a single helium nucleus. The total combined mass of the individual hydrogen nuclei before the reaction is greater than the mass of the helium nucleus. The mass lost as a result of this chain reaction is turned into energy according to Einstein’s famous equation, E = mc2 (Chapter 39). Consider the first part of the chain reaction in which two hydrogen nuclei (each a single proton) fuse. Figure P8.56A shows the potential energy curve of a two-proton system. The energy in this graph is given in keV, where “eV” is the abbreviation for the unit electron-volt and 1 eV = 1.6 × 10−19 J. When the protons are more than about 2 fm (2 × 10−15 m) apart, the potential energy is positive. When the protons are close together, the potential energy is negative, and the protons are fused. Figure P8.56B shows a close-up of the potential energy curve when the protons are far apart.

  1. a. What is the minimum mechanical energy required for the two protons to fuse? Give your answer in keV.
  2. b. The mechanical energy of an average two-proton system in the Sun is around 2 keV. What is the minimum distance between the protons in such a system?
  3. c. Explain why it seems impossible for fusion to take place in the Sun. Note: Of course, fusion must take place in the Sun. Although it seems impossible according to classical mechanics, quantum mechanics (Part VI) makes fusion possible. According to quantum mechanics, the seemingly impossible is merely improbable, and even events with a low probability of occurrence may still happen. Because there are so many protons in the Sun, there is a good chance that at any moment many of them will fuse.

Chapter 8, Problem 56PQ, The Sun is powered by nuclear fusion. In each chain reaction, four hydrogen nuclei fuse together to

Weekly leaderboard

Home
Homework Help 3,900,000
Physics 110,000
Start filling in the gaps now
Log in