Concept explainers
The reason due to which the helium fusion in a star’s core, that releases energy, actually lead to a decrease in its luminosity. Also, mention the name of these stars in the HR diagram.
Answer to Problem 1CC
Solution:
The energy released from core helium fusion enlarges the star's core, which decreases the
Explanation of Solution
Introduction:
Most stars have the same chemical composition but the difference in stars depend on the two primary properties like their surface temperature and luminosities. These two properties vary from one star to another. H-R diagrams or hertz sprung- Russell diagrams are a graphical tool used by astronomers for the classification of stars according to their spectral type, luminosity, temperature, color, evolutionary track, and temperature.
Explanation:
During helium fusion in core, the surrounding hydrogen fusion in the shell of the star provides most of the red giant’s luminosity and helium flash is not observed. The core expands when core helium fusion begins as a result of which the temperature of the core decreases. The cooling of the core indirectly cools the surrounding hydrogen fusing shell, due to which the shell liberates energy slowly. Hence, the luminosity decreases a bit after core helium fusion begins.
The contraction of star’s external layer is because of the slow energy release. While shrinking, there is an increase in the star’s surface temperature. So, the evolutionary track of the star moves to the left in the H-R diagram. In this stage, the changes in luminosity are very low due to which a horizontal shift can be seen in the evolutionary track, along the path which is referred as the horizontal branch.
Conclusion:
The fusion of helium enlarges the core which decreases the energy of both the hydrogen fusion in the shell and the helium fusion in core. This decrease in rate of energy decreases the luminosity of the stars. These stars are called horizontal branch stars.
Want to see more full solutions like this?
Chapter 20 Solutions
EBK LOOSE-LEAF VERSION OF UNIVERSE
- 1. A charge of -25 μC is distributed uniformly throughout a spherical volume of radius 11.5 cm. Determine the electric field due to this charge at a distance of (a) 2 cm, (b) 4.6 cm, and (c) 25 cm from the center of the sphere. (a) = = (b) E = (c)Ẻ = = NC NC NCarrow_forward1. A long silver rod of radius 3.5 cm has a charge of -3.9 ис on its surface. Here ŕ is a unit vector ст directed perpendicularly away from the axis of the rod as shown in the figure. (a) Find the electric field at a point 5 cm from the center of the rod (an outside point). E = N C (b) Find the electric field at a point 1.8 cm from the center of the rod (an inside point) E=0 Think & Prepare N C 1. Is there a symmetry in the charge distribution? What kind of symmetry? 2. The problem gives the charge per unit length 1. How do you figure out the surface charge density σ from a?arrow_forward1. Determine the electric flux through each surface whose cross-section is shown below. 55 S₂ -29 S5 SA S3 + 9 Enter your answer in terms of q and ε Φ (a) s₁ (b) s₂ = -29 (C) Φ զ Ερ (d) SA = (e) $5 (f) Sa $6 = II ✓ -29 S6 +39arrow_forward
- No chatgpt pls will upvotearrow_forwardthe cable may break and cause severe injury. cable is more likely to break as compared to the [1] ds, inclined at angles of 30° and 50° to the vertical rings by way of a scaled diagram. [4] I 30° T₁ 3cm 3.8T2 cm 200 N 50° at it is headed due North and its airspeed indicat 240 km/h. If there is a wind of 100 km/h from We e relative to the Earth? [3]arrow_forwardCan you explain this using nodal analysis With the nodes I have present And then show me how many KCL equations I need to write, I’m thinking 2 since we have 2 dependent sourcesarrow_forward
- The shear leg derrick is used to haul the 200-kg net of fish onto the dock as shown in. Assume the force in each leg acts along its axis. 5.6 m. 4 m- B Part A Determine the compressive force along leg AB. Express your answer to three significant figures and include the appropriate units. FAB = Value Submit Request Answer Part B Units ? Determine the compressive force along leg CB. Express your answer to three significant figures and include the appropriate units. FCB= Value Submit Request Answer Part C ? Units Determine the tension in the winch cable DB. Express your answer with the appropriate units. 2marrow_forwardPart A (Figure 1) shows a bucket suspended from a cable by means of a small pulley at C. If the bucket and its contents have a mass of 10 kg, determine the location of the pulley for equilibrium. The cable is 6 m long. Express your answer to three significant figures and include the appropriate units. Figure 4 m B НА x = Value Submit Request Answer Provide Feedback < 1 of 1 T 1 m Units ?arrow_forwardThe particle in is in equilibrium and F4 = 165 lb. Part A Determine the magnitude of F1. Express your answer in pounds to three significant figures. ΑΣΦ tvec F₁ = Submit Request Answer Part B Determine the magnitude of F2. Express your answer in pounds to three significant figures. ΑΣΦ It vec F2 = Submit Request Answer Part C Determine the magnitude of F3. Express your answer in pounds to three significant figures. ? ? lb lb F₂ 225 lb 135° 45° 30° -60°-arrow_forward
- Foundations of Astronomy (MindTap Course List)PhysicsISBN:9781337399920Author:Michael A. Seeds, Dana BackmanPublisher:Cengage LearningStars and Galaxies (MindTap Course List)PhysicsISBN:9781337399944Author:Michael A. SeedsPublisher:Cengage LearningAstronomyPhysicsISBN:9781938168284Author:Andrew Fraknoi; David Morrison; Sidney C. WolffPublisher:OpenStax
- Stars and GalaxiesPhysicsISBN:9781305120785Author:Michael A. Seeds, Dana BackmanPublisher:Cengage Learning