Questions tagged [newtonian-mechanics]
Newtonian mechanics discusses the movement of classical bodies under the influence of forces by applying Newton’s three laws. For more general concepts, use [classical-mechanics]. For Newton’s description of gravity, use [newtonian-gravity].
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How to calculate the changing radius and velocity of a particle in a cyclotron?
I've tried coming up with logic to relate both the variables but end up getting a recursive value for velocity in terms of instantaneous radius, every time.
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Is a torque of 0.26 Nm (2.5 kgf*cm) enough to turn the stick (see)? [closed]
I found this:
“The electric motor has a power of 6 W, the torque of the 50KTIZ-30 model is 0.26 Nm (2.5 kgf*cm). The gearbox output shaft rotation speed is 30 rpm.”
Will he cope with the task of ...
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Work done by variable force dependent on $x$ and $y$ [closed]
I have problem with exercise below:
A force with the following components acts on the object: $F_x = 3(x^2- y)$, $F_y = 2$. The force moves the material point
along the sides of a triangle whose ...
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Rope over an un-ideal pulley in an Atwood's machine [closed]
Please consider a pulley with a taut rope over it and two objects (with different masses m1 and m2) hanging on each side. The pulley is not negligible - it has a mass Mp.
In the solution to a problem ...
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How does moving the pericenter affect the apocenter?
A perfectly circular orbit of a constant height (distance from the center of mass of the orbited planet) around a perfectly spherical planet with smooth surface and no gravitational anomalies will ...
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I am facing trouble understanding the concept of torque about an axis [closed]
The torque about a point has a clear definition, $\vec{r} \times \vec{f}$, and I read somewhere that the torque with respect to an axis is the same for any point on the axis, but I don't understand ...
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Why is energy conservation not valid here? [closed]
I was solving this question and I faced a problem :
See the problem is I know the conventional way of impulse momentum and energy conservation to solve this question but ,
I do not know why applying ...
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Analyzing uniform circular motion with Lagrangian mechanics
Consider swinging a ball around a center via uniform circular motion. The centripetal acceleration is provided by the tension of a rope. Now, is this force a constraint force? If it is, since it is ...
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Friction when a body just begins to move [closed]
I was solving a mechanics problem from a book called Problems in Physics for IIT-JEE , the solution for a question is something I'm not convinced with. It goes like-
In the arrangement shown in the ...
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Can someone please help me understand how muscles move bones? [closed]
In the picture below I have published my attempt at understanding how muscles move bones.
My conclusions are that
A muscle cannot span a bone, otherwise if it just pulls on the extremities of a bone ...
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Can the same rough surface provide frictional force on opposite directions for translation and rotation of a sphere under a tangential external force?
I came across a question which says:
"A force $F$ acts tangentially at the highest point of a sphere of mass
m kept on a rough horizontal plane. If the rolls without slipping ,
find the ...
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What is the acceleration of non-zero mass rope between two bodies moving with a force? [closed]
if I have two bodies are linked with a non-zero mass rope that makes curved shape due to gravity, what is the acceleration of each of the rope
the first body
the second body
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Is torque due to gravity about the center of mass zero?
I know torque due to Fg is zero on a level rod. However if the rod is tilted like below, is the torque still zero? The pivot point is on the center of mass.
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Will work done be zero when Tesla car goes uphill and comes back downhill? [closed]
If we are going uphill using Tesla car, it uses energy from the battery however when we come downhill it charges the battery, I am not sure if the charge produced while driving downhill will be equal ...
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A mass $m$ is kept on a platform which starts from rest with constant acceleration $g/2$ upwards, work done by normal reaction on block in time $t$ [closed]
Here we are considering pseudo force in normal reaction but we don't consider psuedo accl in case of finding the displacement why
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Where do exerted forces come from?
I think my confusion stems from this: if a book is resting on a table I understand that the force of gravity acts on the book and as it is in equilibrium, the table exerts a force equal in magnitude ...
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Problems on laws of motion with wedge [closed]
I Have two questions =
what will be force (Fy) ?
if box is moving then magnitude of normal reaction from ground will remain same or some component of force will go in moving direction?
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Why is the work done by static friction on a rolling object zero (or is it)?
My question is: are these three statements correct?
(1) The net work on an object that rolls without slipping can be exactly divided into a "work on the center of mass" and a "work ...
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Derivation of the function for the position of a particle given that a constant force acts on the particle which always points to fixed point [closed]
A particle of mass $m$ is moving with initial velocity v. A constant force F acts on the particle in a direction which always points to a fixed point P. If initially the direction of v was ...
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How stable are orbits of light objects around twin large bodies?
I know the two-body problem has a stable solution and the three-body problem does not.
In the case that there are two comparable large bodies (twin planets) in a stable mutual orbit, what happens to a ...
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Work-Energy Theorem but Work is $F.S_{COM}$ (Extended)
From the definition of Work Done, we know it is $\vec F . \vec s$ , where $\vec s$ is displacement of point of application of force.
Everything was alright until I read these texts from Kleppner and ...
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Is there a way to theoretically estimate the restitution coefficient of a rubber ball?
Let's consider a rubber ball like the ones shown in the picture:
When dropped onto the floor, the ball will rebound, but it won't regain its initial height.
The restitution coefficient is defined as ...
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How to make a wrist pulse switch relay? [closed]
I want to create a mechanical 'make break' circuit or relay that can be mounted on the wrist near the radial artery such that it should make or break the connection w.r.t the pulse. In other words, ...
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How does vibration transmitted through a horizontal surface cause the uniform rotary motion of objects sitting on the surface?
On top of my washing machine is an aluminium tray, which holds various objects (used in the making of hot drinks). When the machine is on the final spin phase of its programme, it vibrates strongly. ...
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Why does a ball tied to a spring move outwards when rotated (ground frame)?
Suppose a bob or a ball is tied to a spring which in turn is pivoted to a certain point on a table as shown, if the ball is given velocity $v_o$ perpendicular to spring it moves in circular motion and ...
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Why are missiles rotating in space?
Watching the Starship launch today I noticed it's actually doing some full rotations. Why isn't it controlled? and why does it happen?
I have read that it's the same for military missiles too
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What will happen if 10kg massed hydrogen ballon is released in air?
Generally, a hydrogen balloon would float when released in air, but what will happen when that hydrogen balloon has a mass of 10kg. Is it the density that decides whether an object floats in air or ...
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Can joint stiffness be controlled by actuators?
I am a software developer running this simulation and have some trouble understanding the underlying physical problem. My description of the problem is therefore probably not perfect, but I hope ...
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How to model torque and linear force of collisions for a simple 2D physics engine [closed]
I'm attempting to make a simple physics engine but chat gpt for the most part has been unreliable.
I have a 2d space (vacumm).
For simplicity I would like to model collisions between extended circular ...
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Is the net force on centre of mass always equal to the external force applied on one block of a two block system connected by a spring?
I came across a question which says-
"Two blocks of equal mass m are connected by an unstretched spring and the system is kept at rest on a frictionless horizontal surface. A constant force F is ...
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Kinetic energy in different reference frame [closed]
Suppose a system with a $1 \textrm{kg}$ and a $2 \textrm{kg}$ ball. The $1 \textrm{kg}$ ball is moving at $1 \textrm{m}/\textrm{s}$ relative to observer. In this case, the $E_{\textrm{k}}$ of the ...
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Analysis of 2-body problem with changing mass and velocity [closed]
I am researching on a non-physical application, which in my current understanding, looks analogous to the motion of a body whose mass, position and velocity change over time and is also affected by ...
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What's the path of charged particle around a circular magnetic field?
I'm trying to simulate electromagnetic fields. At the moment I'm exploring only magnetic fields (I know you can't have it without electric charge).
Anyway, I created a current carrying wire (just a ...
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Infinite angular velocity paradox
This paper is based on a question by Puk asked Jun 28, 2020 on the Stack Exchange Physics site, Newton's 2nd law for rolling motion with changing moment of inertia, about a long, hollow, rigid but ...
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Resulting pressure of batteries in series [closed]
Hi everyone we are working on a battery project and have the following question. What is the influence of stacking battery cells next to each other in a battery module on the resulting pressure ...
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Direction of $\hat\theta $ and $\hat r$ in pendulum [closed]
When trying to find $\alpha (t)$ , I have $F_{mg}=mg(\cos{\alpha}\hat r + \sin{\alpha}\hat\theta)$. Using the assumption the rope remains the same length, I get the ODE (from the equation of ...
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Euler 6 DoF Equation Continuum Modeled-Derivation
I derive the translational equations of motion like the following,
$$\frac{d\vec{P}}{dt} = \frac{d}{dt}\int_v \vec{dp_i} = \frac{d}{dt}\int_v \vec{v_i}dm = \frac{d}{dt}\int_v \vec{v_i}\rho_idV$$
...
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Time taken for an object to fall [duplicate]
Time taken for an object to fall is generally given by $$t=\sqrt{\frac{2h}{g}}.$$ But this is only true under the assumption that gravitational acceleration is constant. With variable gravity what ...
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Mechanics (SHM) [closed]
In a system (shown in the figure), thread "N" from the lower end of which a ball "A" is suspended, to which, in turn, a ball "B" is suspended by a thread of length $l$. ...
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Coriolis acceleration for wind at some latitude and longitude on the surface
I was trying to do an alternative general expression for Coriolis acceleration to the one explained on Wikipedia which I find not too intuitive and too simple calculation wise.
Supposing the $z$ axis ...
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A wheel is rolling up the (horizontal) street. Will it roll forever with the same speed? [duplicate]
A wheel is rolling up the street (which is "horizontal", not an incline). The center of mass of the wheel has velocity V in the forward direction, relative to the ground. (Let's ignore air ...
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Elliptical orbit, work done by gravity
Consider two points (A & B) on one half of an elliptical orbit. Satellite moves from point A to B. I want to calculate the work done by the gravitational force, but I DO NOT WANT to use energy ...
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Non-Uniform Circular Motion applied to horizontal tracks [closed]
Given that a car moves on a circular path with a length of approx 59m (radius of 19) , with a given value of final velocity (17m/s)), initial velocity (11m/s) and the angle that's subtending θ(178°), ...
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How can bodies with constant velocity exert a force? [duplicate]
Consider a wind speed of $80kmh^{-1}$ towards the west, when this wind comes into contact with another body, it will obviously exert some force. However, what is the magnitude of this force? $F=ma$, ...
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Escape Velocity from Moon to escape Earth-Moon System
So the escape velocity at Earth is roughly 11.2 km/s, but with the escape velocity of the moon it says that it is 2.38 km/s but since the moon is orbiting the Earth, wouldn't the effective escape ...
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How is Newton's 3rd law applied in rocket propulsion?
I'm really wanting to get into physics more and I've had this question for a while. I do know a bit about rocketry as I think it's pretty cool but I'm still struggling to understand how Newton's 3rd ...
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Height of weight dropped vs launch distance
Say you have a system where a weight drops on an air source, which blows on the ball, launching it. Are there any relations or formulas between the forces at work here? For instance, would there be an ...
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How does moving the launch area forward impact the area of impact?
If we launch an object in some way, and it lands at distance x, if we move forward the launching mechanism y units forward or backwards, will the landing distance also move forwards or backwards y ...
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How does the distribution of floor choices of your co-passengers affect your time of arrival in an elevator?
Note: This is a wiki post.
Suppose you are late for a meeting and you have to take an elevator. The floor choice of your fellow passengers influences how late you will reach your destination. If ...
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Simulate 3g of acceleration on a test specimen [closed]
I am trying to simulate 3g of acceleration on a ventilation duct as it will utltimately be installed on a ship and I need to make sure it can withstand the platform movements which I estimated, with a ...