Lifting/breaking an object with circular motion

Click For Summary

Discussion Overview

The discussion revolves around the forces involved in lifting and breaking objects through circular motion, specifically in the context of centripetal force experiments. Participants explore the mechanics of tension in a rope and the forces acting on a washer and a nut during vertical circular motion.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant questions what force pulls the washer upwards when it is whirled, suggesting that tension must equal the centripetal force created by the washer's weight.
  • Another participant argues that increasing the speed of the stopper creates more tension in the rope, which can lift the washer, challenging the initial assumption about the relationship between tension and weight.
  • A participant raises a concern about how to create more tension without applying additional force, noting that the washer gains potential energy as it rises, implying a net force must be doing work against gravity.
  • There is a discussion about the forces involved when whirling a rod with a nut attached, with one participant stating that the faster the rod is whirled, the greater the force exerted on the nut, leading to potential breakage.
  • Another participant emphasizes that when the tension in the string exceeds a certain limit, it will break, indicating that increased speed results in higher tension.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between tension, centripetal force, and the forces acting on the washer and nut. There is no consensus on how tension is generated or the specific forces at play in these scenarios.

Contextual Notes

Participants discuss the mechanics of circular motion without resolving the assumptions about force application, tension dynamics, and the conditions under which the rope or string may break.

great_scott
Messages
9
Reaction score
0
i have two questions i think are asking almost the same thing.

1) in this typical centripetal force experiment; there are a stopper mass attacthed to one end of a rope and a washer attached to the other end of the rope. as the washer hangs straight down, i start whirling the stopper. after a point, the faster i whirl it, the more the washer goes up. the question is what is the force that pulls the washer upwards? i assume the tension must always be equal to the centripetal force that is created by the weight of the washer so it shouldn't be enough to beat the weight of the washer to lift it.

2)there is a nut or something breakable on an end of a rod and as you whirl the rod vertically keeping the nut in a circular motion. as you do it faster and faster you observe the nut breaks or at least gets damage soon or later. what is the force that breaks the nut?

thanks.
 
Physics news on Phys.org
great_scott said:
the question is what is the force that pulls the washer upwards?
The string tension.
i assume the tension must always be equal to the centripetal force that is created by the weight of the washer so it shouldn't be enough to beat the weight of the washer to lift it.
Don't assume that the tension just equals the weight of the washer. By spinning the stopper faster, you create more tension, which raises the washer.
2)there is a nut or something breakable on an end of a rod and as you whirl the rod vertically keeping the nut in a circular motion. as you do it faster and faster you observe the nut breaks or at least gets damage soon or later. what is the force that breaks the nut?
The faster you whirl the rod, the greater force it must exert on whatever is attached to it. Eventually, something breaks.
 
how do i creat more tension with no additional force? and obviously as the washer goes up it gains some more potential energy so there has got to be a net force that does some work against gravity by raising the washer?
i can actually put it that way what force makes the rope break when i whirl an object attachted to the rope fast enough? let's say vertically and above my head.
 
great_scott said:
how do i creat more tension with no additional force? and obviously as the washer goes up it gains some more potential energy so there has got to be a net force that does some work against gravity by raising the washer?
Tell me how you get the stopper to go faster.
i can actually put it that way what force makes the rope break when i whirl an object attachted to the rope fast enough? let's say vertically and above my head.
When the string tension gets too high, the string breaks. You are pulling on the string with a greater force as you twirl it faster.
 

Similar threads

High School A scenario of non-uniform circular motion
  • · Replies 4 ·
Replies
4
Views
938
Undergrad Why can centripetal force balance out gravity?
  • · Replies 23 ·
Replies
23
Views
4K
Undergrad Why Does Friction Provide Centripetal Acceleration in Circular Motion?
  • · Replies 37 ·
2
Replies
37
Views
5K
High School Confusion while trying to build intuition of centripetal force
  • · Replies 15 ·
Replies
15
Views
4K
Graduate Solving for Constant Centripetal Acceleration: Understanding Spiral Motion
  • · Replies 5 ·
Replies
5
Views
4K
Undergrad Origin of Centripetal force when the net force toward the center is 0?
  • · Replies 8 ·
Replies
8
Views
3K
High School Uniform circular motion - origin of speed
  • · Replies 4 ·
Replies
4
Views
2K
Undergrad Direction of friction of each wheel and total moment when a car turns
  • · Replies 6 ·
Replies
6
Views
3K
Undergrad Find period of circular-orbiting source based on max observed freq
  • · Replies 1 ·
Replies
1
Views
2K
Undergrad How do we provide centripetal force in this situation?
  • · Replies 16 ·
Replies
16
Views
3K