What is Horizontal: Definition and 978 Discussions

The horizontal branch (HB) is a stage of stellar evolution that immediately follows the red-giant branch in stars whose masses are similar to the Sun's. Horizontal-branch stars are powered by helium fusion in the core (via the triple-alpha process) and by hydrogen fusion (via the CNO cycle) in a shell surrounding the core. The onset of core helium fusion at the tip of the red-giant branch causes substantial changes in stellar structure, resulting in an overall reduction in luminosity, some contraction of the stellar envelope, and the surface reaching higher temperatures.

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  1. T

    How to calculate the horizontal distance traveled by a bouncing ball?

    Does anyone have a link to an explanation (or could explain themselves) on how to calculate the total HORIZONTAL distance traveled by a bouncing ball? I have filmed and analysed (plotted the points) of a few trajectories, so I have the values, I just need to explain why i got those values and...
  2. N

    Sliding time before a ball begins to roll on a horizontal surface

    Homework Statement A ball is released along a horizontal surface with a co-efficient of friction Us at a speed V. Find the time it takes for the ball to start rolling (leave the moment of inertia as I). Homework Equations Quite a few, all of them are stated in my working (that I...
  3. S

    Horizontal spring and wood block energy and equilibrium question

    Homework Statement A 200 g wood block is firmly attached to a horizontal spring. The block can slide along a table where the coefficient of friction is 0.40. A force of 10 N compresses the spring 18 cm. If the spring is released from this position, how far beyond its equilibrium position will...
  4. M

    Horizontal Tangent in Parametric Equations: Finding & Understanding

    If the tangent is horizontal, it is where the tangent is zero. In single var. calc. that would be at max. or min. for example. I am confused about what horizontal tangent refers to when I am given a parametric equation. E.g. At what value of t does x=t^2 -t and y=t^2 +t have a horizontal...
  5. M

    PS4 horizontal on or elevated from wood

    I don't have a heat meter to test this so I just want to ask from a physics perspective what is more likely to be more effective. I noticed that my PS4 gets quite hot. I have it horizontal on a wooden surface. Ideally on top of a metal surface probably it would have been better since heat...
  6. M

    Horizontal deflection of a vertically loaded cantilever

    Hello you clever people, I'm having a bit of a logical problem with the deflection of a simple uniform cantilever beam loaded with a downward force on the free end. My intuition is that the beam would do something like this: But most literature, and my mechanics of solids course at uni...
  7. R

    Cube tipping on horizontal surface

    Homework Statement A cube of mass m and side 2a is held on one of its edges on a horizontal surface. It is released from this position and allowed to tip. Find an expression for the angular velocity of the cube as its face strikes the surface of the table in the following cases: a) the...
  8. T

    Determining Sin wave horizontal shift 'C' value

    Find the equation of a sine function with its first positive maximum point at (pi/5,8) and its next minimum point at (7pi/10,-2). With the sin form as y=a*sin[b*(x-c)] + d I found: a=[max-min]/2 = 5 b= 2pi/period= 2pi/(2*[max-min])=2 d=max+min/2=3 I am having troubles determining...
  9. C

    MHB Velocity & Horizontal Distance of Person on Water Slide

    a person slides down a water slide that is 61 m long and has a slope angle of 24 degrees and the end is a ramp with a height of 3.66 m with an angle of 30 degrees to the horizontal determine the magnitude and direction of the velocity of the person when they just fly away from the ramp and the...
  10. 1

    Springs question - vertical versus horizontal stretching

    Springs question -- vertical versus horizontal stretching... So I know hooke's law well enough and I understand the spring constant and it's vertical applications where force equals displacement times some constant. What I am unsure of is to what degree this all applies to a horizontal stretch...
  11. C

    Shaft - find natural frequency of horizontal shaft with bearings

    shaft -- find natural frequency of horizontal shaft with bearings how to find natural frequency of horizontal shaft with bearings at either sides, using (Ansys-classic). Please reply, Thank you.
  12. T

    Spring with mass on horizontal surface

    Homework Statement A 2.00 kg object on a horizontal frictionless surface is attached to a spring with a spring constant 1000 N/m. The object is displaced from equilibrium 50.0 cm horizontally and given an initial velocity of 4.0 m/s away from the equilibrium position. (a) What is the...
  13. W

    Physics of Climbing vs. Walking (Horizontal)

    Hi, please forgive my ignorance here; I barely have just a basic undergrad. training in physics: I was trying to see if we can use physics to determine how much harder it is (say, by amount of energy/calories spent; maybe someone can suggest a better measure? ) to climb stairs, given the slope...
  14. B

    Fluid dynamics in horizontal pipe

    There's a figure that comes with the question but I'm having trouble attaching it so I will describe it the best I can. There is a large cylinder labeled the reservoir. A horizontal pipe is connected near the base of the reservoir and it is open at the other end so fluid flows out (point B)...
  15. P

    Help with horizontal velocity

    Help pleasezz with horizontal velocity Homework Statement Ms. Rob launches a rocket from the school roof at an angle of 45 degrees and observes it's horizontal range. What other angle could she launch the rocket so that it lands in the same spot, ignoring air resistance? Homework...
  16. A

    MHB Equation for the horizontal asymptote.

    How would you find the equation for the horizontal asymptote of the following exponential function?: g(x) = -2f(2x - 6) Let f(x) = 4^x
  17. A

    Propeller rotating in horizontal plane

    Hello, I have a project whereby I am designing a toy that spins a horizontally positioned propeller, then releases it. After releasing it, the propeller gains height, but moves somewhat away from the operator of the toy. Is the direction of airflow through the propeller vertically? If...
  18. MarkFL

    MHB JustWar's question at Yahoo Answers regarding horizontal tangents

    Here is the question: I have posted a link there to this thread so the OP can view my work.
  19. B

    Analysis of Billiards Ball Motion Following a Horizontal Queue Impact

    [b]1. Encountered with cue to a massive billiards ball, which is initially at rest, see figure uploaded. The ball has radius R and mass M. The queue hits with force F horizontally into the bale height h above the table, and the shock lasts a very short time Δt. It is reported that the moment of...
  20. homer

    Concentric conducting spherical shells cut by a horizontal plane

    Homework Statement A conducting spherical shell of outer radius a and inner radius 3a/4 is cut in two pieces via a horizontal plane a distance a/2 above the center of the spherical shell, as shown in Figure 1. Let us label "A" the upper part of the shell and "B" the lower part of the shell...
  21. S

    Physics question - Forces on a mass on horizontal surface

    Physics question -- Forces on a mass on horizontal surface Homework Statement A 2.5 kg mass at rest on a horizontal surface is acted upon by an applied horizontal force of 150 N. A frictional force of 100 N acts on the mass. How much work is done on the mass? Homework Equations I'm not...
  22. A

    How can I find work, horizontal force, and time contact?

    Homework Statement For a physics project, i need to answer a bunch of questions after conducting an experiment with projectile motion. I have answered most of them. The questions with the work shown are here: http://i.imgur.com/JmYPMC9.png I cannot answer number 10 and 11, because I don't...
  23. C

    Vertical & Horizontal Components of Acceleration (Upward Force)

    Homework Statement In the picture below, we see a scene from the days of yore. This is called a tow path and the situation is that a barge is being towed by some horses along the side of a canal. Let's say the horses pull with 6200 N of force at an angle of θ=16∘. If the barge has a mass of...
  24. G

    Calculating Horizontal Distance: Solving for Time and Velocity

    Homework Statement http://s27.postimg.org/pqmx061qb/Screen_Shot_2014_02_17_at_11_42_12_PM.png Homework Equations vix=vfx ax=0 viy=0The Attempt at a Solution i found that t = 0.639s not sure where to go from there
  25. P

    Horizontal bar is used to support a 75-kg object between two walls

    Homework Statement A horizontal bar is used to support a 75-kg object between two walls. The equal forces F exerted by the bar against the walls can be varied by adjusting the length of the bar. Only friction between the ends of the bar and the walls supports the system. The coefficient of...
  26. W

    Two basic types of horizontal stabilizer systems

    There are two basic types of horizontal stabilizer systems on most general aviation aircraft. Horizontal stabilizer with elevator, and or horizontal stabilator. If the horizontal stabilator system that is on most piper aircraft and some high performance fighter aircraft, then why are so many...
  27. N

    Show that the horizontal range is 4h/tan(theta)

    Homework Statement A projectile launched at angle Θ to the horizontal reaches maximum height h. Show that its horizontal range is 4h/ tan Θ.The Attempt at a Solution tapex = vi sin Θ/g tfull trajectory = 2vi sin Θ/g h(tapex) = h = vi^2 sin^2 Θ/2g x(tfull trajectory) = x = \frac{vi^2 sin (2Θ)}{g}
  28. N

    Horizontal range of 2 different angles

    Homework Statement Show that, for a given initial speed, te horizontal range of a projectile is the same for launch angles 45° +\alpha and 45° - \alpha The Attempt at a Solution x1 = vi cos (45° + \alpha) x2 = vi cos (45° - \alpha) tcomplete trajectory = 2 vi...
  29. N

    Answer check-derive a general formula for horizontal displacement

    Homework Statement Derive a general formula for the horizontal distance covered by a projectile launched horizontally at speed vi from height, h. The Attempt at a Solution vyf = vyi -gt t = vyf/g x = vxi .t = vi cosΘ (t = vyf/g) = [vi^2 sinΘcosΘ]/g
  30. M

    Heat transfer between enclosed parallel horizontal plates

    Homework Statement I am curious about the situation of heat transfer between parallel horizontal plates in an enclosed space (particularly with the lower plate being higher temperature and subjected to a steady heat flux) with the enclosure itself being composed of a fictional "perfect...
  31. C

    Revolution about horizontal and vertical lines

    Homework Statement Use shell method to find volume. y=x+2 y=x^2 rotate about the x-axis 2. The attempt at a solution I cannot seem to solve this. I thought this was the way to solve it, but I don't understand if I am missing something crucial. This is how I set up the...
  32. E

    Horizontal and Vertical Tangents for Polar Equation

    Homework Statement Find the points at which the following polar equation has horizontal and vertical tangents: r2 = 4cos(2θ)Homework Equations \frac{dy}{dx} = \frac{r'(θ)sinθ + r(θ)cosθ}{r'(θ)cosθ - r(θ)sinθ} Horizontal Tangent: \frac{dy}{dθ} = 0; \frac{dx}{dθ} ≠ 0 Vertical Tangent...
  33. B

    Horizontal force outward inclined plan.

    Homework Statement A block of 5 kg is on plane that is inclined of 37°, an outward (It is not directed toward the plane but it drags the the block horizontally away) horizontal force of 50 N is applied on the . The friction coefficient of that plane is 0,30. What is the total force that is...
  34. C

    MHB Understanding Horizontal Asymptotes

    I'm stuck at understanding why +c is the horizontal asymptote. Can someone please explain this? I get that the vertical asymptote is relating to (x+b), because the denominator cannot=0. But why does this kind of graph have a horizontal asymptote to begin with?
  35. G

    Applied force in horizontal direction on block on a inclined plane.

    Homework Statement 10kg block on a inclined plane (32degrees) (frictionless) and an applied force 120N horizontally. What is acceleration? Homework Equations Fnet = ma The Attempt at a Solution mgsin32 = 51.9N (from mg) From applied force, in the same plane, we have xcos32=120...
  36. Spinnor

    Feynman diagram for gluon exchange, time up, gluon horizontal.

    Consider the Feynman diagram below from, http://hyperphysics.phy-astr.gsu.edu/hbase/particles/expar.html where I assume time runs upwards and the gluon in the graphic runs horizontal and is labled as a green_antiblue gluon. If the gluon runs horizontal can one still label a gluon as being...
  37. B

    Calculating Horizontal Forces on Frictionless Surface

    I have a surface that has minimal to no friction and I have used an elastic band to set my disc off from one end of the surface to the other. It crashes into the wall the other side and rebounds. How can I work out the acceleration. Am I right in assuming that at first the disc travels at a...
  38. H

    Incompressible fluid in horizontal test tube

    Homework Statement An incompressible fluid with density ρ is in a horizontal test tube of inner cross-sectional area A. The test tube spins in a horizontal circle in an ultracentrifuge at an angular speed ω. Gravitational forces are negligible. Consider a volume element of the fluid of area...
  39. K

    Find the tension in the horizontal cable that supports the boom

    Homework Statement A crane in a marble quarry is mounted on the rock walls of the quarry and is supporting a 2000 kg slab of marble as shown in the figure. The center of mass of the 900 kg boom is located one-third of the way from the pivot end of its 15-m length, as shown. Given...
  40. H

    The horizontal distance the train will move before its speed reduces?

    Homework Statement A 60,000 kg train is being pulled up a 1% gradient by an engine exerting 3 kN. The frictional force opposing the motion of the train is 4 kN. The train’s initial speed is 12 m/s. Through what horizontal distance will the train move before it’s speed is reduced to 9 m/s...
  41. C

    Frictionless horizontal then ramp?

    Homework Statement An object of mass m and initial speed v0 sliding on a horizontal frictionless surface encounters a frictionless ramp. To what vertical height will the object rise before coming to rest? Homework Equations .5mv^2 = .5mgh The Attempt at a Solution I used above...
  42. J

    Proof of the stiffness of the horizontal component of a spring

    Homework Statement Suppose a spring with forces F=k*z. Find the equivalent stiffness of a horizontal spring, where the spring and its horizontal equivalent is separated by theta degrees. The horizontal equivalent presumably will have a force F(x)=k(x)*x Homework Equations F =...
  43. H

    Horizontal Pulley Question [Forces]

    Homework Statement An object is hanging by a [mass-less] string on a [mass-less] pulley from a cart on a desk with a mass of 1.8 kg. The cart has an acceleration of 2.5 m/s^2. Calculate the mass of the hanging object given that: a) There is no friction. b) There is a frictional force of...
  44. marellasunny

    Gyroscopic effect in a horizontal axis IC engine

    My tutor says Henry Ford opted for a horizontal-bed IC engine for the Model-T as this would avoid having any gyroscopic effects(normally associated with a vertical oriented engine). My question is,how does it matter if the engine cylinders are oriented horizontally or vertically?since the...
  45. D

    How can horizontal force affect power in scientific experiments?

    Hello, not looking for much help on the problem, rather I am seeking someone to try and solve this problem and tell me I'm not crazy that the so called "correct" answers above are wrong.
  46. M

    Horizontal and vertical parity check

    Hello. I need help in detecting error. The question in the attached file is to first fill in the blanks with vertical and horizontal parities. Secondly, it says that there is an error in the circled part. My problem is, how do I find that error and why is there an error? In the second image, I...
  47. S

    Linear Dynamics Help: friction and horizontal force

    Homework Statement I've been having some problems trying to do a few lab questions for my physics class, I'm not very good at it but I do try to make the best of it so anyone that's willing to help me give me any pointers would be awesome. I have two physics problem and I'm supposed to do them...
  48. H

    Solving for Building Height and Time in Horizontal Projectile Motion

    Homework Statement A ball is thrown horizontally from the top of a building and lands 20.0m away from it. If the ball is initially thrown at a velocity of 10.0m/s, how high is the building? How long does it take for the ball to reach the ground? Homework Equations dv = Viv * t + 1/2a *...
  49. D

    Effect of speed on horizontal displacement in projectile motion

    Homework Statement Question: Provided all else is equal, if a ball is thrown at half the original speed will it travel half as far? Homework Equations Δx = vΔt The Attempt at a Solution In projectile motion, the time of flight will be the same no matter the horizontal...
  50. M

    Question about limits and horizontal asymptotes

    Homework Statement Find the limit and any horizontal asymptotes: lim 4/(e-x) x→∞ Homework Equations Principle 1: A limit defines a horizontal asymptote whenever x→∞ or x→-∞. Principle 2: If a limit goes to ∞ or -∞, there won't be a horizontal asymptote. The Attempt at a Solution lim...
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