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. A

    Calculating Distance Wood Block Travels After Spring Released

    A 280000-kg wood block is firmly attached to a very light horizontal spring, as shown in the figure . The block can slide along a table where the coefficient of friction is 0.30. A force of 22 N compresses the spring .18m . If the spring is released from this position, how far beyond its...
  2. N

    Pressure In a Horizontal Pipe -

    Pressure In a Horizontal Pipe - Please Help! Homework Statement The pressure in a section of horizontal pipe with a diameter of 2.40 cm is 143 kPa. Water flows through the pipe at 2.90 L/s. If the pressure at a certain point is to be reduced to 101 kPa by constricting a section of the pipe...
  3. P

    Shopping Carts, Finding Horizontal Force

    Correct? Please let me know if my logic is off. Given Problem A shopper pushes a 6.1 kg shopping cart up a 13° incline, as shown in the figure. Find the magnitude of the horizontal force, F, needed to give the cart an acceleration of 1.51 m/s2. Relevant equations F = ma Fy = F1cos13°...
  4. Z

    What horizontal distance can a painter climbing a ladder before it slips

    This is for an online homework assignment that apparently is not crediting the proper answer. I'm just curious to know if I got this right or if I'm way off. Thanks in advance.Homework Statement If the coefficient of static friction is 0.362, and the same ladder makes a 61.0° angle with...
  5. J

    Angle and Frequency in Horizontal Circular Motion

    Homework Statement What happens to the angle below the horizontal as frequency increases? (in horizontal circular motion) Homework Equations The Attempt at a Solution I think that it would decrease, because your speed is increasing, but I don't know if I'm right
  6. r-soy

    Find an equation for the horizontal tangent to the curve y=x-3root x

    Hi a ) find an equation for the horizontal tangent to the curve y=x-3root x b) What is range of values of values of curve's slope ? c ) What is range of values of curve ? number a already I solved but my queation now in b and c ----- I try to solve b) to get curve's slope must...
  7. A

    Horizontal tangents via implicit differentiation

    Homework Statement Find the points (if any) of of horizontal tangent lines on : x2 + xy + y2 = 6 Homework Equations n/a The Attempt at a Solution So far I've concluded that I must find the points at which dy/dx = 0. I've solved for dy/dx and arrived at dy/dx = (-2x-y)/(x+2y)...
  8. M

    Vertical and horizontal subspace

    where in the definition of vertical subspace we understand that the notion of canonical vertical vector: a vertical vector is a vector tangent to the fiber. ?
  9. K

    Derivative and horizontal tangent help

    Derivative and horizontal tangent help! Homework Statement Determine the point at which the graph of the function has a horizontal tangent line. Homework Equationshttp://www.webassign.net/cgi-bin/symimage.cgi?expr=f%28x%29%20%3D%20%288%20x%2A%2A2%29%2F%28x%2A%2A2%2B8%29and f(x)=x/...
  10. K

    Derivative and horizontal tangent help

    Derivative and horizontal tangent help! Determine the point at which the graph of the function has a horizontal tangent line. http://www.webassign.net/cgi-bin/symimage.cgi?expr=f%28x%29%20%3D%20%288%20x%2A%2A2%29%2F%28x%2A%2A2%2B8%29 and f(x)=x/ root2x-1endroot
  11. P

    Friction (horizontal) Applied Greater Force than Equilibrium

    Homework Statement When you apply a horizontal force of 44 N o a block, the block moves across the floor at a constant speed (μk = μs). When you apply a force of 50 N, what is the magnitude of the horizontal component of the force that the floor exerts on the block? Homework Equations...
  12. C

    A ball is shot from the ground into the air and horizontal distance

    [b]1. The problem statement, all variables and given/known da A ball is shot from the ground into the air. At a height of 9.7 m, the velocity is observed to be v = (7.4)i + (5.1)j in meters per second (i horizontal, j upward). Homework Equations What will be the total horizontal distance...
  13. P

    Finding minimum V and angle given horizontal and vertical travel

    Homework Statement a mountain climber plans to jump from A to B over a crevasse. Determine the smallest value of the climbers initial velocity Vo and the corresponding value of the angle alpha so he lands at B Homework Equations A to B is 1.8m horizontal distance and B is lower than A...
  14. P

    How to Calculate Projectile Motion Using Horizontal and Vertical Equations?

    Zero Launch Angle Lab We used a spring loaded gun and shot a ball out of it. Here's the data: three trials: 1.78 seconds 1.34 seconds 1.39 seconds the distance traveled was the same for each trial: 2.98 meters the height is 1.04 m FIND: 1. percent error on time. 2...
  15. A

    Which Points on the Curve y = sin(2x) + 2 sin(x) Have a Horizontal Tangent Line?

    Find the x-coordinate of all points on the curve y = sin(2x) + 2 sin(x) at which the tangent line is horizontal. Consider the domain x = [0,2π). f'(x)=2cos2x+2cosx
  16. A

    Find the points on a horizontal line

    Question: Find all points on the graph of the function f(x) = 2 sin(x) + (sin(x))2 at which the tangent line is horizontal. Consider the domain x = [0,2π). f'(x)=2cos x+2sinxcosx...i think No idea where to go after this...
  17. I

    Why do the Horizontal components cancel in E-Field

    Homework Statement Plane X=0 has a uniform charge density, \rhos while plane X=a has -\rhos. Determine the electric field intensity in region X<0. Homework Equations E=\frac{Q}{4\Pi\epsilon0R2}aR The Attempt at a Solution I already know the answer to this question. What I'm...
  18. J

    Solving Frictionless Horizontal Motion: Find Block's Speed

    Homework Statement A 5.86 kg block located on a horizontal frictionless floor is pulled by a cord that exerts a force F = 10.00 N at an angle = 35.0° above the horizontal (x-axis). What is the speed of the block 3.70 seconds after it starts moving? Homework Equations Fcos() - ma = 0...
  19. D

    Horizontal Range and Maximum Height of a Projectile

    Homework Statement A ball is thrown vertically up from y=0 at time t=0 with vinitial=v0j. Show that the time it takes for the ball to reach the ground is twice the time it takes to reach its maximum height. Homework Equations h=(vi2sinthetai)/2g R=(vi2sin2thetai)/g The Attempt at...
  20. C

    Find the points at which the graph has vertical and horizontal tangents

    PRObLEM SOLVED> :)
  21. A

    Analysis of Person Diving into Pool w/ Uniform Horizontal Beam

    Homework Statement An 80kg person is preparing to dive into a pool. The diving board is a uniform horizontal beam that is hinged to the ground at point A and supported by a frictionless roller at D. B is the point directly under the center of gravity of the person. The distance between A to B...
  22. W

    Connection, horizontal lift, and berry phase

    i am now reading the PRL paper by simon on berry phase under adiabatic approximation, the wave function evolves as \langle \psi | d/dt | \psi \rangle=0. how to relate this equation to the connection on a fiber bundle? how to understand that the wave function is parallel transported?
  23. W

    Vertical and horizontal subspace of a vector space T_pP.

    suppose we have a principle fiber bundle P at a point p \in P we have the decomposition T_pP=V_pP + H_pP it is said that the vertical subspace V_pP is uniquely defined while H_pP is not i cannot understand this point the complement to a unique subspace is surely unique, i think. it is a...
  24. T

    Horizontal component of the superhero’s displacement?

    1.A superhero flies 340 m from the top of a tall building at an angle of 22 ◦ below the horizontal. What is the horizontal component of the superhero’s displacement? Answer in units of m. What is the vertical component of the super- hero’s displacement? Answer in units of m. 2...
  25. M

    Power screw horizontal applicaion FBD

    Hello, I have been trying to set up a free body diagram for a power screw in a horizontal application. Every example I find they are using a power screw to lift or lower a load not move it left to right. I have attached the example from the textbook, along with my work so far...
  26. F

    Circular motion at end of string in horizontal plane

    Suppose a mass m suspended from a string of length l is undergoing uniform circular motion in a horizontal plane, with angular velocity ω. Calculate the centripetal acceleration a. If T is the tension in the string, and θ the angle the string makes with the vertical, then the vertical and...
  27. A

    What horizontal force is required to accelerate the block

    A block of mass 4.0kg rests on a horizontal surface. What horizontal force is required to accelerate the block at 5.0m/s2 if the coefficient of kinetic friction is 0.25?
  28. N

    Object dragged at an angle across a horizontal plane

    Homework Statement Let's say I had this object that someone was dragging at an angle across a horizontal plane. I am only given the angle to the horizontal, the mass of the object, and the coefficient of kinetic friction between the object and the surface. How do I find the applied force...
  29. I

    Why Does My Graph Cross the Horizontal Asymptote y=1?

    Homework Statement Find the horizontal asymptote(if there is one) using the rule for determining the horizontal asymptote of a rational function for (x^2+x-12)/ (x^2 -4)Homework Equations The Attempt at a Solution the degree of the numerator and denominator are both 2. Y=(An)/(Bn) Y=1/1 Y=1...
  30. J

    Can Horizontal Force Lolcats Enhance Your Workout?

    Lolcats lollllllllllllllllllllllllllllllll
  31. V

    Relation between mass and circular horizontal velocity

    I am doing an investigation on circular motion and have chosen to study the relationship between mass and its circular horizontal velocity Can anyone tell me what the actual relationship between the 2 variables is so that i have a good reference point. Other websites do not seem to offer a...
  32. F

    Calculating Max Speed of 0.3 kg Mass on Horizontal Spring

    Homework Statement If a mass of 0.3 kg is attached to a horizontal spring system with a spring constant of 32 N/m^2 is stretched 0.2 m from its relaxed length, what is the maximum speed the mass will attain when released from this position? The Attempt at a Solution i thought all...
  33. C

    Calculating Spring Constant for Horizontal Oscillation of a Mass

    Homework Statement Consider a 2.5kg mass oscillating at the end of a spring, with the frequency of 1.0Hz. The motion of the mass extends through 0.04m. Homework Equations Determine the spring constant- The Attempt at a Solution I can't find the right equation to set up this...
  34. T

    Horizontal distance travelled at given time

    I need to figure out how far an object has traveled at a given time. For example purposes the object will be thrown with a velocity of 30 m/s and at an angle of 30 degrees. I've figured out the distance/peak height/peak time/time of flight but I don't quite understand how to figure out the...
  35. D

    Calculating required pump pressure to maintain flowrate in a uniform horizontal pipe

    Homework Statement I am having trouble with calculating the required pump pressure in a horizontal water pipe, 3Km long. i know that the flowrate is 600Kg/s, average velocity 5.6m/s, cross-sectional area of pipe is 0.107143m^2 and losses due to friction average 0.002 per meter Homework...
  36. R

    What is the Pressure Calculation for a Horizontal Pipe with Vertical Tubes?

    Homework Statement Water (η = 1.00E-3 Pa*s) is flowing through a horizontal pipe with a volume flow rate of 0.0121 m3/s. As the figure below shows, there are two vertical tubes that project from the pipe. Assume that H = 0.0424 m and L = 0.679 m. Homework Equations No idea how to...
  37. S

    Finding Spring Constant in horizontal direction

    Hello All, Again, a funny question is raised: From the following site, I can determine the spring constant K for a compression spring at vertical axis. http://www.roymech.co.uk/Useful_Tables/Springs/Springs_helical.html However, I wonder is there any equation to find the spring constant...
  38. L

    Write an equation of each horizontal tangent line to the curve.

    Homework Statement Write an equation of each horizontal tangent line to the curve. Homework Equations y = 2y^3 + 6x^2y - 12x + 6y = 1 y' = (4x - 2xy) / x^2 + y^2 + 1) The Attempt at a Solution Well, horizontal tangent line means the derivative equals zero. Thus, 4x - 2xy = 0...
  39. A

    Find which value of x horizontal Tangent Line

    Find which value of x...horizontal Tangent Line Homework Statement What is given is F(x)= -4/(x-3)(x+4) and the problem asks for to find the value of x where f(x) has a horizontal tangent line.Homework Equations I read somewhere else on these forms that using the quotient rule is the key, and...
  40. M

    Pendulum with horizontal spring

    Homework Statement A 5kg sphere is connected to a thin massless but rigid rod of length L=1.3 m to form a simple pendulum. The rod is connected to a nearby vertical wall by a spring with a spring constant k= 75N/m, connected to it at a distance h=1.1 m below the pivot point of the pendulum...
  41. P

    Projectile Motion - Horizontal Component

    A rock is thrown off a 100.0m cliff upward at an angle of 20o to the horizontal. It has an initial velocity of 15ms-1 and strikes the rocks below. Find how far away the rock is from the base of the cliff. I calculated total time of flight (projectile parabola + 100m vertical descent)...
  42. T

    Horizontal Asymptote of f(x)=x^3+1/x-1: Is it y=x^2?

    When the power of the leading coefficient of the numerator of a rational function is a lot greater than the power of the leading coefficient of the denominator , ie f(x)=\frac{x^3+1}{x-1} The horizontal asymtote is y=x^2 according to the book . Is that true ? Is there any proof for this ...
  43. A

    Horizontal Projectile Motion Speed

    Homework Statement A projectile is fired horzontally from a height of 1.5 m with a velocity of 100 m/s [E]. Ignoring any effects of friction... a) How much time will elapse between the projectile being fired and hitting the ground? b) What will be the horizontal distance from the point...
  44. T

    Horizontal tangent points (implicit differentiation)

    Homework Statement Find the points on the lemniscate: 2( x^2 + y^2 )^2 = 25( x^2 - y^2 ) where the tangent is horizontal Homework Equations Horizontal tangent: y' = 0 The Attempt at a Solution I got the correct gradient of y' = [ 50x - 8x^3 - 8y^2 ] / [ (8x^2)y + 50y + 8y^3 ]...
  45. D

    Horizontal range of a projectile

    Homework Statement A ball is tossed from an upper-story window of a building. The ball is given an initial velocity of 7.80 m/s at an angle of 15.0° below the horizontal. It strikes the ground 6.00 s later. (a) How far horizontally from the base of the building does the ball strike the...
  46. C

    Frictionproblem Yoyo on a horizontal plane.

    I have just studied a problem regarding a yoyo being pulled along a horzontal plane and where the task is to find which way the frictionforce from the ground on the yoyo is acting. I have seen the solution to it, but I find it confusing and would therefore like to ask some questions about it...
  47. R

    Horizontal acceleration of an aircraft

    Homework Statement A Physics student wishes to measure the maximum horizontal acceleration of an aircraft as it accelerates down the runway. To do this the student measures the angle that a weight on a string is deflected from the vertical direction when the plane accelerates (see diagram)...
  48. S

    How Do You Calculate Horizontal Angles in Surveying?

    Homework Statement I have been told to work out the Horizontal Angle when given the Horizontal reading of face left and face right at different sights. For example: Face Left---------Face Right A - 26 12 48--------206 12 59 C - 172 23 08--------352 23 17 I am unsure how to work out the...
  49. I

    Tangent, Horizontal and Vertical Lines at the Pole

    Help me understand exactly what is going on here. I'll put up an attempt at my solution: Find the tangent lines at the pole r = sin5o, [0,pi] (note: o represents theta) Equation: dy/dx = [f'(o)sino + f(o)coso]/[f'(o)coso - f(o)sino] f(o) = sin5o f'(o) = 5cos5o plugging everything...
  50. C

    Finding acceleration of a block being pushed up a ramp by a horizontal force

    Homework Statement A block is pushed up a frictionless incline by an applied horizontal force as shown. The acceleration of gravity is 9.8 m/s2 . What is the magnitude of the resulting acceleration of the block? Answer in units of m/s^2. Homework Equations...
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