Questions tagged [newtonian-mechanics]

Newtonian mechanics covers the discussion of the movement of classical bodies under the influence of forces by making use of Newton’s three laws. For more general discussion of energy, momentum conservation etc., use classical-mechanics, for Newton’s description of gravity, use newtonian-gravity.

Filter by
Sorted by
Tagged with
0
votes
0answers
48 views

Unequal forces acting on two blocks connected by a string [closed]

Two blocks A and B are separated by some distance and tied by a string as shown in the figure. Find the tension in the string. I can see that maximum value $f_1$ can attain is $7 N$ and the maximum ...
0
votes
2answers
59 views

Vertical component of friction

If we have a car of mass $m$ sliding around a banked curve of angle $\phi$ with some coefficent of friction ${\mu}$, then the normal force will be $$Ncos\phi= mg + {\mu}F_{g}\sin\phi$$ But this ...
0
votes
3answers
54 views

Equilibrium of a body in torque problem

I was watching a video about torque in which the task was to find the force $F_2 $ when a body is in equilibrium. The person in the video said that in order for the body to be in equilibrium, two ...
0
votes
0answers
67 views

Good Source to Understand Angular Momentum [duplicate]

I am looking for a good source to understand angular momentum. I know the basics but I am looking for a sound in-depth knowledge like directions of angular momentum, when it is not parallel to angular ...
0
votes
4answers
72 views

How to understand force given an inconstant mass?

I am wondering about what force really is after I have looked up wikipedia, where there is stated that $F=ma$ only holds to be true for a constant $m$. For inconstant mass force is: $$F=\frac{dp}{dt}=...
1
vote
3answers
141 views

U-turn in Deep Space

While writing a physically realistic game ( "Asteroid Defender" ) a physical question came up whether Diag.1 or Diag.2 or Diag.3, correctly depicts reality. In deep space (away from other celestial ...
1
vote
1answer
117 views

Extensible string on a pulley

Suppose we have an extensible massless string satisfying Hooke's Law, tied to a wall at one end and going over a 'fricional pulley'. Now if we tie the other end with a mass 'M', the total length of ...
7
votes
2answers
1k views

Shouldn't ball has to move in the circle even after cutting the rope by which it was attached?

Since the tension force is a central acting force, the torque on an orbiting ball about that center is zero. But if the rope is cut down during motion the torque would still remain zero. This would ...
-1
votes
0answers
29 views

Two values of coefficient of friction, Contrary to the fact that μ only depends upon nature of surfaces in contact [closed]

Experimental Setup: We have a block resting over a ramp of variable angle of inclination. We wanted to measure the coefficient of friction at different angles upto limiting angle (exceeding which ...
0
votes
1answer
37 views

Does asymmetric rigid body experience torque-free precession?

I know that a top (or any axis symmetric body) experience torque-free precession. and I know that asymmetric body, with 3 different dimensions has stable rotation when the angular velocity is near the ...
-4
votes
0answers
50 views

Where's the mistake here? [duplicate]

Newton's second law states that The force on an object in an inertial frame of reference is proportional to it's rate of change of momentum. Now if we consider the rate of change d(mv)/dt=mdv/dt+...
0
votes
1answer
63 views

Calculating moments of inertia for partially filled cylinders [closed]

I'm planning on doing an experiment with cylinders of equal length and constant density but different solid fills. For example, a filled cylinder, $75\%$ filled, $50\%$ filled, $25\%$ filled, and a ...
1
vote
1answer
31 views

Tensions in objects other than ropes

Can you have tensions in objects other than strings and rope? suppose you have a piece of paper and you pull at it from both ends it becomes sort of taut similar to how a rope does when you pull at ...
2
votes
1answer
36 views

Tension in a ring rotating about its own axis

A ring of mass m and radius R is placed on a smooth horizontal table and is set rotating about its own axis in such a way that each part of the ring moves with a speed v. What is the tension in the ...
4
votes
1answer
646 views

Prerequisites for Halliday Resnick Walker

I am in grade 10. I have developed an interest in physics but unfortunately I do not know/ have not studied calculus yet as my school board does not recommend it in grade 10. I have a copy of ...
0
votes
2answers
23 views

Simple harmonic motion on a vertical spring

Say we have a spring attached vertically to a wall. Now, let's assume that we attach a mass to the spring, but we do not let the spring extend just yet (we could hold the mass on our palm for example)....
0
votes
1answer
47 views

Help with the problem of moving two fingers along a yardstick

The following problem is taken from an MIT homework assignment: Hold a yardstick horizontally on your index fingers and slide your fingers together smoothly. The stick slides first on one finger, ...
0
votes
1answer
54 views

Motion of Particle Described by Given Equation

I encountered a problem wherein I was given that the electric lines of force in a region varies as $$x^2+y^2=1$$ A charged particle was initially at rest at $(1,0)$. I had to answer whether the ...
1
vote
1answer
21 views

The impact and collision principle

A particle P of mass 3m is moving in a straight line with speed u on a smooth horizontal table , a second particle Q of mass 2m is moving with speed 2u in the opposite direction of P on the same ...
19
votes
8answers
14k views

Why I think tension should be twice the force in a tug of war

I'm going to provide my argument for why I think the tension in a rope should be twice the force exerted on either side of it. First, let's consider a different example. Say, there is a person named <...
213
votes
18answers
56k views

Why does kinetic energy increase quadratically, not linearly, with speed?

As Wikipedia says: [...] the kinetic energy of a non-rotating object of mass $m$ traveling at a speed $v$ is $\frac{1}{2}mv^2$. Why does this not increase linearly with speed? Why does it take so ...
1
vote
3answers
55 views

Energy Loss in Inelastic Collision

If we take a tennis ball and drop it from a certain height above the ground on earth, it collides inelastically, with the maximum height it can reach reducing after each collision due to loss of ...
1
vote
2answers
319 views

Why doesn't the vacuum of space rip the Earth, or other celestial bodies, like the Sun, apart?

Since vacuums are a lower pressure than the atmosphere of the earth(and probably many or all other planets) then why doesn't the vacuum of space rip the earth apart or suck all the gasses on it away ...
0
votes
1answer
144 views

What does a scale accelerating on an incline read?

I was watching an online video lecture about dynamics, and then I came across this brain teaser, and I've been thinking it over for a couple of hours but can't seem to find the solution. I hope ...
0
votes
1answer
39 views

Normal force in this example? [on hold]

My question here is, why there is no Normal Force, because object A is on the ground. Is it because the normal force only exist when we move object along some path?
1
vote
1answer
61 views

How is a quartic oscillator solved in classical mechanics?

Quantum mechanically, a quartic anharmonic oscillator with potential $$V(x)=\frac{1}{2}m\omega^2x^2+\lambda x^4$$ is dealt with perturbation theory- the approximate energies $E_n$ and energy ...
1
vote
0answers
39 views

Friction at high speeds

I am reading a book which mentions that frictional force is not exactly proportional to the normal force at high speeds. Quoting: Once the bodies slip on each other frictional force is, $kN$. This ...
0
votes
2answers
207 views

What effect will a space-elevator have on Earth's rotational speed?

If you (or e.g. a skater) spin on the spot with your arms outstretched you spin at a given speed, but when you retract your arms you spin much faster, extending your arms again will slow the spin down....
1
vote
1answer
33 views

Gravitational two-body problem: Same period

Specifically in circular orbits of two stars around the center of mass: How can I show that the periods are equal?
-1
votes
1answer
90 views

Derivation of the K.E. formula without the work-energy theorem (or proof of the work-energy theorem without the kinetic energy formula)

All of the derivations I have seen for the kinetic energy formula have relied on the fact that work is the change in kinetic energy, something like the one found here: How to prove equation of kinetic ...
2
votes
1answer
139 views

What happens when one uses a blender in zero gravity?

I was recently told by a friend that using a blender type apparatus in a zero gravity environment will act like a centrifuge instead mixing properly. Is this the case? Furthermore, can anyone provide ...
13
votes
3answers
3k views

How is angular momentum conserved for the orbiting body if the centripetal force disappears? [duplicate]

When the centripetal force on an orbiting body disappears (e.g. if it the body is a ball and the force was exerted by a string and the string rips, or, more unrealistically, if the body is the earth ...
1
vote
1answer
187 views

Circular motion with two particles attached: Seeking intuition

A narrow groove is cut along a diameter in the surface of a horizontal disc with center $O$. Particles $P$ and $Q$, of masses $0.2\,\text{kg}$ and $0.3\,\text{kg}$ respectively, lie in the groove, ...
0
votes
1answer
69 views

What are the equations of motion for a pendulum in $n$ dimensions?

Consider a pendulum formed of a light rod of length $l$ and a point mass $m$. At the pivot the pendulum experiences friction with coefficient $b$, and an agent can exert torque $\tau$. In 2 ...
1
vote
3answers
67 views

In non-uniform circular motion are centripetal acceleration and tangential acceleration independent of each other?

In non-uniform circular motion, the centripetal acceleration and tangential acceleration are perpendicular to each other, but does that mean that they don't affect each other because centripetal ...
1
vote
1answer
104 views

What if Newton's bucket had been a sphere?

My question involves a modification of Newton's bucket experiment. If a sphere filled (say) one-third or one-half with water is rotated very very fast, will the water eventually spread out across and ...
1
vote
0answers
35 views

Validity of Newton's second law in a non-inertial reference frame

Suppose two observers are mutually interact through gravitational force (assuming they are alone at space). If the reference frame is fixed in one of the observers could the observer in the reference ...
1
vote
0answers
27 views

Elastic (Young's) modulus and shear modulus derived from interatomic potential

Based on figure shown here, a theoretical elastic modulus can be derived by considering the interatomic potential and taking the derivative of the potential energy with respect to the distance (x-...
-1
votes
0answers
17 views

(NLM) Find Acceleration of Both Blocks so that they won't lose their contact [on hold]

'a' and 'x' have numerical values. All pulleys are attached to some mass. Direction Of Acceleration is Right(+x axis)
0
votes
1answer
69 views

Newton's third law in magnetic in magnetic fields

Say I have a charged particle moving through a magnetic field perpendicular to it. It will experience a force, but according to Newton third law Every force has an equal and opposite reaction. So ...
0
votes
1answer
136 views

Why does pseudoforce act in opposite directions when we move from ground frame to the centre of mass?

In the solution of above question, they solved it by moving from ground frame to the frame of centre of mass. But we know that, to move from one frame to another ,we have to subtract the mass-...
1
vote
1answer
53 views

Ideal geometry for a shaft terminating thrust bearing

Following this PyDy example, I'm trying to understand the problem set 3.10 of the book: Kane, Thomas R., and David A. Levinson. Dynamics, theory and applications. McGraw Hill, 1985. page 272 (292 ...
0
votes
0answers
42 views

Do objects actually fall at the same rate? [duplicate]

The force of gravity takes the mass of both objects into account. For the sake of argument we are doing the experiment on the moon. The moon + the hammer have a greater combined mass than the moon ...
1
vote
2answers
152 views

How does conservation of energy work?

I understand that the law of conservation of energy states that energy cannot be created or destroyed, it can only change from one form to another. This means that the total energy before a certain ...
0
votes
1answer
33 views

Tangential Motion of an Object Attached by a Radial Elastic String [closed]

A toy car travels in a horizontal circle of radius 2a, kept on track by a radial elastic string of unstretched length a. The period of rotation is T. When the car is speeded up the string stretches ...
5
votes
4answers
3k views

Can human push Earth away from the Sun?

It's said the earth is approaching the sun. Can we push it away little by little? Although we can emit rocket towards the sun, but it's too expensive to make a rocket: So I think maybe we can ...
2
votes
1answer
310 views

The dynamics of a cornering wheel

Can a rolling wheel create a side force without first rotating on a vertical axis? There is something wrong with the way we describe how a cornering vehicle wheel creates a cornering force. I think ...
0
votes
3answers
55 views

Weight and Inertia (are they related?)

R. Feynman wrote in his lecture (The Feynman Lectures on Physics: Chapter-9) "Weight and inertia are proportional, and on the earth’s surface are often taken to be numerically equal, which causes a ...
-6
votes
0answers
26 views

New problem in classical mechanics [duplicate]

the question is,Two small weights P and Q connected by a flexible but I extensible cord of length l are hung over a perfectly smooth circular cylinder of radius r if l=r and P=2Q find the position ...
0
votes
1answer
56 views

Is it possible to find $\mathbf{v}$ explicitly when $\mathbf{F}$ varies with $\mathbf{v}$?

I have the following problem (NO, this is not to ask for a solution to this problem). A block is placed on a plane inclined at an angle $\theta$. The coefficient of friction between the block and ...