Rope Definition and 835 Threads

  1. duchuy

    Point mechanics -- Tension in a rope from a hanging mass

    Hi, I'm being asked to determine the tension of a rope only knowing that g = 9.8 m.s-2. I understand that in order to calculate tension, I would need to multiply mass with acceleration. But i don't understand how i would in this case. This is the question for reference. Thanks for your help...
  2. V

    Find the tension of a rope with a mass and spring attached

    I'm having trouble with this problem, I think I solved it but I don't know if what I did is right... At first when the velocity is 0 and the spring is at its natural length, there's just gravitational potential energy, so $$E_i=mgh$$ And then, when the mass is released and then reaches its...
  3. B

    Lifting a survivor into a helicopter with a rope

    We have 2 forces affecting the rope: 1. Gravitational force of the body ##=mg## and 2. Force of air = Force of drag= ##F_{AIR}##. The length of the rope is shortening with the velocity ##v_k##. So to figure out the angle ##\theta## I wrote: ##R##= force of rope ##R_x = F_{AIR}## ##R_y = mg##...
  4. narayan821

    Most efficient way to convert rope movement (KE) to rotational KE?

    I've got a moving rope that turns a shaft, which then turns a generator to create electricity. Please point me to a good resource that guides me to perform this efficiently. I would like to maximize the conversion of kinetic energy of the pulled rope system into rotational kinetic energy of the...
  5. N

    Statics Problem -- A bucket suspended between two walls by a rope and pulley

    I approached this question with a free body diagram. my Verticle length of BA is y-2 AC= 15-AB Horizontal length of AC= a; Horizontal length of BA=10-a I have too many unknowns in this problem and I don't know any directions(angle). I know that I should start at the weight and try to resolve the...
  6. M

    B Mass of Hanging Rope: Calculate Easily

    Hi, I have a question about a hanging rope - how do you find it's mass? I've been searching a long time, stumbled across some advanced calculus involving catenary functions and equations, but couldn't quite figure it out.
  7. E

    Change the wavelength in a driven rope?

    I think I know what this problem means, but not sure how can I do quantitative work to solve it. I think only a would work because of friction of string, the reflected waves from the junction between two strings like that. Although, I am not sure how can I build the process, but this was my guess...
  8. MichaelTam

    Tension in a Massive Rotating Rope with an Object

    The whole question is: One end of a uniform rope of mass 𝑚1 and length 𝑙 is attached to a shaft that is rotating at constant angular velocity of magnitude 𝜔. The other end is attached to a point-like object of mass 𝑚2. Find 𝑇(𝑟), the tension in the rope as a function of 𝑟, the distance from the...
  9. jaumzaum

    I Stationary waves in a vertical rope

    I was wondering if we could produce stationary waves in a vertical rope. There is a nice result we can get from a vertical rope that the pulse created from the lower extremity travels upwards with acceleration g/2 and the pulse created in the upper extremity travels downwards with acceleration...
  10. Hamiltonian

    Can Tension in a Whirling Rope be Modeled as a Centrifugal Force?

    the point on the string at a distance r from the pivot is rotating in a circle of radius r and hence a centrifugal force of magnitude mw^2r can be said to act on it where m = (M/L)r . hence the T = centrifugal force T = (M/L)(wr)^2 but my book says otherwise. also can the string with mass be...
  11. Nexus99

    Two masses, a rope and a spring

    I tried in this way: 1) Considering a reference axis oriented downwards: ##M_1:## ## -T + M_1g - k \frac{L_0}{2} = 0## ##T = M_1g - k \frac{L_0}{2} ## 2) ##M_2:## ##M_2g + k \frac{L_0}{2} = M_2 a## ## a = g + \frac{k}{M_2} \frac{L_0}{2} ## 3) ## M_2g \frac{L_0}{2} + \frac{1}{2} k...
  12. LCSphysicist

    A block and a disk connected by a rope

    Basically, there is a gravitational field g and a friction force acting on the cylinder, which does not slip in the plane. The question is, the acceleration of m'. I solve this question basically by this: " m*g*dh*sina + m'*g*dh = m*v1*dv1 + m'*v2*dv2 + I*w1*dw1 " {1} w*r = v1' + v2' So The...
  13. LCSphysicist

    Prisoner sliding down a rope with minimum velocity

    I thought in this equations f is the man's pull\ f + dm*g = T < 600 Where dm is equal to the mass of the string that pull the up part (15-x) after descending x meters. dm/(15-x) = m/15 And, to the man: W - f = Mx'' I can solve this, and i got ~8m/s Is this right?
  14. cwill53

    Mechanics Question- Massive Rope in a Pulley System

    I understand how they might have got to these answers but I'm still kind of shaky on how the mass of the rope plays a role in the tension at point B, and how to mathematically represent the tension at any point along the rope; I know the tension varies because the rope has mass. If I was to...
  15. domingoleung

    Simple Mechanics Problem -- Block connected to a wall by a rope

    (So this is the system given) The following is my analysis: (i) (ii) Well, my problem is - I got a negative acceleration and its quite impossible to have block B moving to the left. So I am wondering if there are any mistakes I've made.
  16. H

    Question on pulleys force and rope pulling

    I have a question about the following 33 and 34. For number 33 I think the answer is B because you have to life up against the force of gravity. While with A you have gravity helping you out. The correct answer is A but I am not sure how. for 34 I think B because you have an extra pulley so...
  17. studentgrade12

    Using a rope to pull a box across a floor (problem with friction)

    I have been trying a couple of problems with forces and i am not getting the answer, I don't understand what i am doing wrong. Can someone please guide me through this question
  18. Frigus

    What causes tension in a rope moving in a vertical circle?

    I don't get how ball moves in a vertical circle,we say tension provides centripetal force to the ball, i have posted a image in this post and in I which I have shown that their is a downward force mg and upward velocity,in this what will cause tension in the rope...from non inertial frame it is...
  19. R

    Find the accelerations of all three blocks and the tension in the rope

    I am thinking about solving it this way. The first three equation is from Newton law. Then the forth one is the constrain equation, after that I simplified the first three equations, and I am thinking about plugging them into the forth equation and solve for T after that I get the value of...
  20. R

    Tension in a rope wrapped around a shaft, pulling in a mass

    Hi everyone, I am thinking of solving it this way. Since Fc=mw^2r. and Fc=T. Then -dT=dmw^2r. where dm=m1(dx/l). and putting the lower at x=l the tension will be T=m2w^2l. Am I doing things right.
  21. R

    System with Pulleys and a Rope That Might Break

    I tried to solve The system of torque as following. I labelled pulley one is the one in the left, and two as the one on the right. α=a/R t1=(-F+T1) R=MR^/2α. So -F+T=Ma/2 for pulley 2 (T1-T2)R=MR^2/2. So T1-T2=Ma/2 for The box T2-mg=ma add the last two equation, to get that T1-mg=Ma/2+ma...
  22. B

    Finding the angle between a wall and a broken rope

    I tried to work out the solution using h. I get a trapezium, but there is always a lack of additional information. I looked up the solution and BAM, there is this simple equation for sinα. I really don't understand how do we get such a solution. I leaned you can use trigonometric functions in a...
  23. Frigus

    B Why Does a Rope Bend? Understanding the Tension and Forces at Play

    Suppose a rope is placed horizontally on a table and rope is perfectly ideal and I pulled the rope from one side in upward direction as rope is ideal so tension should be same, so the particle I pulled should have exerted equal force(due to tension)to the particle which is adjacent to it and...
  24. Jeff Randall

    Calculate Shock Force with Rope Elongation in Excel

    Im new here and don't have a clue for the most part so don't beat up on me too much, but I'm looking for an equation that is simple enough for an idiot like me to understand. I’m looking to build a shock force calculator in Excel (if possible). I’ve found the actual equation online but the...
  25. kepherax

    Tension in Rope using Torque? Did I do this correctly?

    I think I understand but just want to check if I did this correctly, or if there is more to it...
  26. Like Tony Stark

    Finding angular velocity for a rope to be cut

    I wrote Newton's equations for each body (I took ##x## as the axis aligned with the tension) ##m_1##: ##x)f*_1 -T_1+T_2=0## Where ##f*_1=\omega ^2 r_1## ##m_2## ##x)f*_2 -T_2=0## ##x)f*_2=T_2## Where ##f*_2=\omega ^2 r_2## I wrote that ##T_2=1100 N## and solved for ##\omega##, and I got...
  27. Like Tony Stark

    Body connected to two parts of a rope on an inclined plane

    The thing is that my professor said that if the velocity of ##A## is ##400 cm/s##, the velocity of ##B## is ##200 cm/s## because "##B## is connected to two parts of the rope and ##A## is conected just to one part", and he also said that that ##200 cm/s## is the velocity of ##B## with respect to...
  28. Santilopez10

    Finding the Acceleration of a Bag Being Raised by a Rope on a Moving Kid

    So what I did was at first consider the case the kid is below the branch, so that x=0,t=0, then I thought that the length L of the rope should be ##L=2h## because we know the radius from the branch to the kid is just ##x^2+y^2=r^2## and when x=0, y=h. So then I wrote the motion equations for the...
  29. UnPetitGarcon

    Direction of a rope with a ball inside an accelerating box

    A steel washer is suspended inside an empty shipping crate from a light string attached to the top of the crate. The crate slides down a long ramp that is inclined at an angle of 37° above the horizontal. The crate has mass 180 kg. You are sitting inside the crate(with a flashlight); your mass...
  30. Kaushik

    B How Does a Man Accelerate While Climbing a Rope?

    A man tries to climb up a rope with acceleration, ## a ##. What does he actually do to climb up? My Interpretation Let the man pull the rope at point A. So the Point A will pull the man with Tension, ## T ##. But at the same time the man is holding the rope, so there will be some normal...
  31. sumitsumit

    Tension in Rope: Force, Acceleration & Intuition

    i believe there must be some tension while for the force to exert there must be acceleration but my intuition says different
  32. M

    Calculate the tension in a rope attached to a ball in circular motion

    The solution to the problem simply states: "Use of mv^2/r = 2000. T = (2000 + 7500) = 9500N". I don't understand this solution. Nothing more is provided. I don't know how you are supposed to find the radius (in order to use the centripetal force formula) merely from the information provided...
  33. bob45

    I Why do we use the sin x = x approximation for calculating waves on a rope?

    hi, when we try to find the speed of a wave on a rope v = (F/u)^1/2, we use the fact that if the angles are small then sin x = x. I understand the approximation but not WHY we use the approximation. We say delta(Theta) is small (and then amplitude is small) then ... . So the proof is only...
  34. D

    3D Statics problem: Box on an inclined plane constrained by a rope

    Hello Got a following problem. 300N Box on a frictionless inclined plane. The plane itself is in the Z-direction. Box is held by a rope AB and a force in the direction Z. Determine the tension in the rope and the force F. The answers to this problem are 104N and 215NMy question is where do i...
  35. N

    Force exerted on a rope by a falling mass

    Hi I'm wondering, if I had a mass of 10kg and I dropped it 10 metres, how would I work out how much force is exerted on a rope? The rope is made of rubber bands
  36. H

    Tension in a Rope from Lowering Down and Friction Braking Torque at Stop

    (The weight scale = 10 kg). After initial force, now the mass is lowering down at constant speed of 1 m/s. The motor with pulley's radius of 1 meter is exerted 100 Newton m to keep constant V. The motor speed is about 9.55 rpm. * All other weights, inertia and frictions of the system is...
  37. G

    I What's wrong with this approach to the ant on a rubber rope problem?

    Hi. An ant walks with 1 cm/s along a rubber rope with initial length 10 cm that is stretched uniformly with 10 cm/s. Find its velocity at time ##t##. This is a a well-known problem, but I'd like to know what's wrong with the following alternative approach: At time ##t>0##, any point ##x_0## on...
  38. PhysicS FAN

    Objects sliding on inclines without friction (connected by a pulley and rope)

    Homework Statement The 2 objects slid on the incline level without friction. The height difference of the objects at t=0 is 8m. At t'=1.5sec the objects are on the same horizontal level. What is the analogy of M/m? (M is the mass of the left object and m the mass of the right object. *Have a...
  39. A

    Work Check - Centripetal force - Finding Tension in a Rope

    Homework Statement A man, with a mass of 85kg, swings from a vine with a length of 11m. If this speed at the bottom of the swing is 8m/s, what is the tension if g = 10m/s^2? Given: m (mass) = 85kg r (radius) = 11m V (speed) = 8m/s g = 10m/s^2 T = ? Homework Equations Fc (centripetal force) = T...
  40. J

    Tension in a rope at the midpoint

    Homework Statement Calculate Tension (Tp) and (TQ) (P is the mid point) Homework Equations T - mg = maThe Attempt at a Solution For Q (massless rope) Tq - 1.9g - 0.2g - 2.9g = 5a Tq = 5(g+a) Tq = 5 * 10 = 50N Given answer = 50N (Calculation of Tension for Q is clear to me, but I am...
  41. L

    Two pendulums connected with a massless rope

    Homework Statement Two pendulums of same mass and length that oscillate in same horizontal plane are connected with maseless horizontal rope. What is dependence of amplitude of pendulums as a function of time? Homework Equations For harmonic oscilation x=x_0\sin(\omega t+\varphi_0) Kinetic...
  42. Raphael30

    Velocity of a falling folded rope and reaction force

    Homework Statement A rope of length L and mass m is attached to the ceiling and folded at mid length. The free end of the rope is held against the ceiling, then dropped at time t=0. a) Calculate the velocity of the free end as a function of y, its distance from the ceiling. b) Calculate R...
  43. neon495

    How to find the aceleración and the rope forcé Fs?

    << Note -- formatting fixed up by a Mentor >> 1. Homework Statement Please see the attached image for the problem statement. Homework EquationsThe Attempt at a Solution [/B] I uses the formula Fs = Fg1 +Fg2 + Ft1 + Ft2 I asumed the acceleration is equal to (F1+F2)/ m (4,9+19,6)/3 = 4,9ms^-2...
  44. R

    Particle Newtonian Mechanics: Father Pulling 100 lb Sled

    Homework Statement The problem states that there is a father pulling a 100 lb sled with a force of 100 lb at some angle. At what angle does the father have to pull in order for the sled to accelerate at 25 ft/s^2? The coefficient of kinetic friction here is given as 0.04. Homework Equations F...
  45. navneet9431

    Laws of motion while climbing a Rope

    I'm a little confused with the application of laws of motion on a man climbing a rope. Suppose a man of mass Mg is climbing a rope with an acceleration a. Rope is massless. Now if look through the frame of the piece of rope held by the man, there is a force Mg downward by man, ma downward...
  46. Zeke Bevan

    Newton's Third Law Problem: Two masses, a rope and a pulley

    Homework Statement Two blocks are attached to opposite ends of a massless rope that goes over a massless, frictionless, stationary pulley. One of the blocks w/ a mass of 1.5 kg accelerates downward at (3/4)g. A. What is the mass of the other block? Homework Equations There were no given...
  47. M

    Circular Motion Problem: Child swinging on a rope

    Homework Statement A curious child finds a rope hanging vertically from the ceiling of a large storage hangar. The child grabs the rope and starts running in a circle. The length of the rope is 14.0m. When the child runs in a circle of radius 7.0m, the child is about to lose contact with the...
Back
Top