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. ValeForce46

    Cylinder with a horizontal tube (Fluid dynamics problem)

    I'll call ##v_2## the flow speed on the horizontal tube and ##v_1## the lowering speed of the column. Even if the lowering speed isn't negligible, the problem says "...when the plug has been removed", so can I consider the height unchanged? In order to find the force, I need the pressure when...
  2. B

    Need help with horizontal syringe Bernoulli's Principle problem.

    Did I do this problem correctly? I felt like I did this wrong because the answer is suppose to be around 50 m/s.
  3. Shivam

    A smooth massless wedge is pushed by a horizontal Force P....

    Answers- 1,3,4 My attempt, the wedge being massless, there shoul not be any force acting on as it will then have infinite acceleration, so by that i really can't think of how force is applied on pully.
  4. M

    B Is the asteroid belt horizontal or like a dome?

    I see that most planets rotate around the sun in a horizontal circle, except for Pluto. My question is about the asteroid belt and the Kuiper belt. Are they horizontal or like a dome? As in can an object go “above” and “below” them in a totally open space? Also ... is it known and confirmed...
  5. Clout

    Fluid mechanics - pump in a horizontal pipe connecting two pipes

    So when the velocity of v1 and v2 is 0 (because the tanks are much bigger), the bernoulli equation to dh is dh = (dp-dpl)/(rho*g) with dp = Phyd / V = 1000W / 0.01m³/s = 10^5 Pa and rho = 1000 kg/m³ So I am getting first without the pressure loss on the orifice dh = 10^5 Pa / (1000 kg/m³ *...
  6. K

    MHB Finding Horizontal/Vertical Distance Between Two Points in Scratch 3.0

    I am making a Scratch 3.0 game. The shooter sprite is holding a gun slightly off-centre (see images), and I need the bullet to go to the end of the barrel of the gun before traveling forward (as so it would appear the bullet it leaving the gun). The issue is, to do this, I need to find the X and...
  7. R

    Am I understanding horizontal shift properly?

    Homework Statement I mean, it does make sense, if I plot f(x)= x^2 and f(x-1) = (x-1)^2 and find where they intersect the x/y axis, it does make sense. But the book I'm reading (Stewarts) confuses me with the following:"Likewise, if g(x) = f(x-c), c>0, then the value of g at x is the same as...
  8. osten

    Oscillation Problem -- Ball mass on the end of a horizontal spring

    Homework Statement A 200 g ball attached to a spring with spring constant 2.40 N/m oscillates horizontally on a frictionless table. Its velocity is 20.0 cm/s when x=−5.00cm. What is the amplitude of oscillation? Homework Equations f=√(k/m) /2π x(t) = Acos(2πft) v(t) = -2πfAsin(2πft) The...
  9. P

    Pressure changes of a fluid flowing through a horizontal pipe

    If we have a tube of fluid going like it is shown in the picture, and we measure pressure at two points we would get the same value. But the fluid is still going from point A to point B. So is pressure difference not necessary for fluid flow or I made some other wrong assumptions?
  10. Q

    Maximum Horizontal Force of Relativistic Point Charge

    Homework Statement A charge q1 is at rest at the origin, and a charge q2 moves with speed βc in the x-direction, along the line z = b. For what angle θ shown in the figure will the horizontal component of the force on q1 be maximum? What is θ in the β ≈ 1 and β ≈ 0 limits? (see image) Homework...
  11. S

    Comparison horizontal distance in presence of resistance

    Homework Statement A particle of mass m kg is projected under gravity with horizontal and vertical components of velocity U and V. There is horizontal resistance of magnitude mku, where k is constant and u is horizontal component of the velocity at t seconds. No vertical resistance present. (i)...
  12. opus

    Projectile motion problems with No horizontal acceleration

    For projectile motion problems, we say that the horizontal component of the ball's path has no acceleration. The vertical component does, which is due to gravity, but in projectile motion it is true that horizontal and vertical motion are independent of each other. My question is in regards to...
  13. P

    Flag pole finding horizontal force component at hinge.

    Homework Statement A flag pole consists of a 80 kg rod of length L = 2 m with a 10 kg point mass attached to the end. The pole is hinged at the bottom and is tied to a horizontal cable as shown. 1. What is the x-component of F (Fx) exerted by the wall on the flag pole at the hinged point A...
  14. DracoMalfoy

    Torque Problem: Finding the weight of a horizontal bar

    Homework Statement n the diagram below, the horizontal bar has a length of 4m. The force due to the wire angled at 30 degrees is 1200N. What is the weight of the horizontal bar? Homework Equations T=F⊥rThe Attempt at a Solution I know that I need to add the three( the bar, the wire, and...
  15. R

    Finding the horizontal force that the road applies to the car

    Homework Statement Given weight car = 2500lb, acceleration = constant = 2 ft/s^2, radius of curvature at C = 1000 ft, distance between A and B = 1300 ft, distance between B and C = 900 ft Find horizontal force of road on car at B and C. Homework Equations F = ma in normal-tangential...
  16. M

    Oscillating horizontal mass attached to a spring with Friction

    Homework Statement The question is similar to last week’s, except that we will consider how friction may damp the oscillation with time. A block with mass m shown in the drawing is acted on by a spring with spring constant k. The block is pulled distance [x[/0] from equilibrium position (x=0)...
  17. DracoMalfoy

    Spring Potential Energy: Horizontal Spring Problem

    Homework Statement A horizontal spring with a constant of 700N/m is compressed 2cm. A ball of mass 200g is placed in front of the spring. The spring is released. The ball slides along a horizontal track for 10cm while experiencing a frictional force of 0.75N. What is the velocity of the ball at...
  18. alexi_b

    Radial Acceleration on a string

    Homework Statement A ball on the end of a string is whirled around in a horizontal circle of radius 0.250m. The plane of the circle is 1.06m above the ground. The string breaks and the ball lands 1.90m (horizontally) away from the point on the ground directly beneath the ball's location when...
  19. A

    Determining Speed given Horizontal and Vertical Distances

    Homework Statement A girl throws a ball high into the air, and at its highest point it lands on a roof, where it gets stuck. You estimate the ball landed at a height of 21.0m from the ground and a horizontal distance of about 20.0m from where it was thrown. What is the speed that the girl threw...
  20. Boltzman Oscillation

    How does a the vertical force of gravity end in horizontal motion?

    When a stream of water falls perfectly vertical, some water hitting the surface will disperse horizontally. What is the force that causes this? References would be awesome!
  21. C

    Air resistance - freefall and horizontal projectile motion

    We have two identical balls sitting at the same height. One of them is released without applying any force (it falls freely) and the other one is given a non-zero horizontal velocity. Which of them will hit the ground first? The force of air resistance is proportional to the square of the...
  22. H

    Force exerted on the horizontal bottom of the container

    Homework Statement In an empty container, having the shape of a Rectangular Parallelepiped, with width l=0.5m and MN=H=0.4m, and NP=L=0.75M. we poureda mass of mercury =2448kg. T0,T1,T2 have the same section which is 0.2 m^2. we give g=10N/kg, and density of mercury u=13.6 g/(cm^3)...
  23. UMath1

    Is Shear Stress Vertical or Horizontal in I-Beam Webs?

    My mechanics of materials book states that in order for an element to be in equilibrium it must have equal horizontal and vertical shear stresses. However, it also states "The shear stresses in the web of a wide-flange beam act only in the vertical direction and are larger than the stresses in...
  24. Theia

    MHB Max Horizontal Displacement of Projectile and its Velocity at T

    Let x = v_0\cos \alpha _0 t and y = y_0 + v_0 \sin \alpha _0 t - \tfrac{1}{2} gt^2, where v_0 is speed at time t = 0, \alpha _0 is the angle between positive x-axis and initial velocity vector (\alpha _0 \in (0, \pi/2)), t time in seconds, y_0 >0 the y coordinate at time t=0, g acceleration...
  25. jybe

    Work/energy to find horizontal displacement

    Homework Statement A block slides down a frictionless incline (30 degrees above horizontal) for L=1.4m until it meets a horizontal surface with coefficient of kinetic friction 0.3 before coming to rest. Use work and energy to find the distance that the block slides on the horizontal surface...
  26. N

    I Horizontal Force on a trapeze pivot

    -sorry if I got the prefix wrong. I'm working on calculating the forces on a trapeze bar, specifically, what tension I would need on guy wires to resists the horizontal forces on a swinging trapeze. If I could get the horizontal force generated by the the trapeze/pendulum I can do the rest...
  27. Phantoful

    Bead on a string, find y(x) if horizontal velocity is const.

    Homework Statement Homework Equations K = (1/2)mv2 U = mgh W=Fd Integration/Calculus The Attempt at a Solution I'm not sure what I should be doing for this question, if height changes how is it possible that velocity stays the same, according to the conservation of energy (frictionless wire)...
  28. M

    MHB What Are the Steps to Find the Horizontal Asymptote of f(x) = (x^2 - 9)/(x - 3)?

    Find the horizontal asymptote of f(x) = (x^2 - 9)/(x - 3). I need the steps not the solution.
  29. J

    MHB Vertical / Horizontal Displacements

    Hey guys! Firstly, let me start by apologizing if this is completely the wrong place to put this question. As you'll soon tell my maths is... well, questionable at best. Let me just give some context to avoid any assumptions :) I'm starting an OU degree in autumn with my first module being...
  30. B

    Horizontal propagated movement of mechanical wave

    Homework Statement A hand induces a transverse wave in a string by periodically moving up and down. This causes the string to move up and down. This movement propagates through the string producing a series of wavefronts which move towards the fixed wall with a velocity v. How do we...
  31. vAhmed

    Find final velocity in a horizontal projectile motion

    Homework Statement A ball was thrown from a cliff, it reached to the ground after 2.5 seconds. a) Find the height of the cliff. b) Find the horizontal distance the ball reached. Homework Equations Δy = 2⋅g⋅t^2 Vfy = g⋅t √(Vfy)^2+(Vfx)^2 Δx= Vx⋅t The Attempt at a Solution I've found Δy=30.6m...
  32. Martin Peasha

    B Could we launch spaceships from a long horizontal ramp?

    So for a while now I have had an idea for ground to space lift systems. My idea is to build a long electromagnetic launcher for ships underground. No I'm not talking about a tunnel straight towards the center of the Earth or "Down" but level, without taking into consideration the curvature of...
  33. karush

    MHB Cp 3.6.11 A shopper in a supermarket pushes a loaded cart with a horizontal force of 10 N.

    $\tiny{cp 3.6.11}$ $\textsf{A shopper in a supermarket pushes a loaded cart with a horizontal force of 10 N.}$ $\textsf{If the cart has a mass of 30 kg,}$ $\textit{a. how far will it move in 3s starting from rest }$ \begin{align*}\displaystyle ma&=F \\ a&=\frac{F}{m} \\ &=\frac{10N}{30 \, kg}...
  34. R

    Pushing down on a block at an angle on a horizontal table with friction

    Homework Statement Example 2.12 : A block pulled on a horizontal table with friction. A block of weight 100 Newtons rests on a horizontal table. The coefficient of static friction between the block and the table is µs = 0.8. a. If someone pulls on the block with a force F in the direction 37◦...
  35. talknerdy2me

    A ball moves a horizontal circle....

    Homework Statement While a string is attached to a ball and the ball moves in a horizontal circle at a constant speed, does the force change both the direction and speed of the ball? Explain. Homework Equations No equations necessary. The Attempt at a Solution *I think* the force changes...
  36. C

    Velocity of a cylinder on a horizontal plane

    Hi, I appreciate any help. Thanks in advance! Homework Statement The image shows the top view of the set-up. Basically, it is a cylinder (resting on a horizontal plane) with two rods on either side attached in line with the centre of mass of the cylinder. Two pieces of string are then taped...
  37. Pushoam

    Calculating water pressure in a horizontal pipe

    Homework Statement Homework EquationsThe Attempt at a Solution Calculating water pressure using in a horizontal pipe Applying Bernoulli principle, ## p_a + \frac 1 2 \rho gh_a + \frac 1 2 \rho v_a^2 = p_b + \frac 1 2 \rho gh_b + \frac 1 2 \rho v_b^2 ## ## h_a = h_b, v_b = \frac {...
  38. K

    Circular motion, string and ball in a horizontal circle

    A mass m = 0.15 kg is attached to a massless string and rotates at constant speed v = 4 m/s in a horizontal circle of radius 2 m. The tension T (in N) in the string is: (a) 1.1 (b) 1.9 (c) 2.4 (d) 3.3 (e) 4.9 I would assume that first I calculate the centripetal acceleration by using v^2/r =...
  39. I

    Movement of a Body on horizontal surface

    Homework Statement A body that is on a horizontal surface begins to move under the action of horizontal force equal to 60% of its weight. Force acts for a while, then stops acting. Determine the total time of movement if the body has traveled a distance of 24m. Homework Equations [/B] I'm...
  40. M

    Getting the Horizontal Asymptotes

    Homework Statement Homework EquationsThe Attempt at a Solution I understand there is no vertical asymptotes and can usually get the horizontal ,but can't understand with the exponential.
  41. W

    Excel: Inserting many Horizontal rows in same Cell

    Hi all, I have been trying unsuccessfully to figure out how to insert many horizontal rows into the same cell in Excel: I have gone over many sites, asked people, all sorts of key combinations, without success. Any ideas you know work, please? Thanks.
  42. I

    Moving along a horizontal surface (no friction)

    At a force of 40N, the body moves along a horizontal surface with an acceleration of 2m/s^2 and under the action of 50N with an acceleration of 3m/s^2. What is the mass of the body? F1 = 40N a1 = 2m/s^2 F2 = 50N a2 = 3m/s^2 _____________ m=? 2. Homework Equations As there's no...
  43. J

    Wheel rolling on a horizontal surface

    Homework Statement Homework EquationsThe Attempt at a Solution Since the wheel is rolling , vcm=ωr , acm = αr The wheel is in pure rotation about the point O where it touches the surface . The point P is a distance 4/3 from the bottom point . Angular acceleration of the point = 3 rad/s2...
  44. F

    Finding the period of an object moving in horizontal circle

    Homework Statement A small mass m is suspended from a string of length L. The body revolves in a horizontal circle of radius R with a constant speed v. Find the speed of the body and the period of the revolution. Homework Equations ΣFx = Tx = mV^2/r Period = (2πr)/V The Attempt at a...
  45. SciencyBoi

    A block placed in a horizontal hollow cylinder

    Homework Statement A block is placed inside a horizontal hollow cylinder. The cylinder is rotating with constant angular speed one revolution per second about its axis. The angular position of the block at which it begins to slide is 30° below the horizontal level passing through the center...
  46. Andrea Vironda

    Quantifying Acceleration in Non-Perpendicular Torque Systems

    Hi, I'm making some confusion about statical and dynamic behavior. if i have a body distant from the rotational axis, i have a static torque for maintaining it on position (i suppose ##\vec g \perp \vec r##). But if a supply more torque i accellerate the body. How can i quantify this...
  47. S

    Question about Angular Motion in a horizontal plane

    For finding the critical speed or the minimum speed in a question for a vertical plane, you take either the friction or the contact (normal) force to be 0, so F=W However, for a horizontal plane, like spinning something around in a circle, you can still do F=W to find the critical speed or the...
  48. A

    Calculating Distance for a Train on a 1% Grade

    Can anyone help with the following question, please? 1. A 60,000kg train is being pulled up a 1 percent grade (it rises 1m for each horizontal 100m). The friction force opposing the motion of the train is 4,000N. Initial speed of the train is 12 m/s. Through what horizontal distance will the...
  49. A

    Relationship between Launch Angle & Horizontal Distance

    Homework Statement How to prove the correlation between launch angle (<45°) and horizontal displacement. Independent Variable: Horizontal distance Dependent Variable: Launch Angle (Important) Controlled Variable: Firing velocity [90 m/s] Another problem is, with the data that I have...
  50. C

    Acceleration of a box across a rough horizontal plane

    Not sure if I'm doing this right would love input Consider a box m=50kg which is being pulled on a rough, horizontal surface by a person using a rope . Assume that the person is applying a force of T=150N on the block , the rope makes an angle of 30 degrees with the horizontal and the...
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