The rate of change of velocity of a body per unit of time.

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1answer
2k views

Can we determine the force an object exerts by its mass and acceleration?

I understand that the objects acceleration is determined by the force exerted on it, and that the force exerted on it is determined by its acceleration. But, does an object's (named A) acceleration ...
1
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1answer
66 views

Calculate speed from accelerometer

I am trying to use my accelerometer on my mobile device (smart watch to be specific) to calculate a persons arm swing speed. The data returned from the accelerometer is in $m/s^2$. Since the ...
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0answers
21 views

Are these Kinematics Equations Correct? [on hold]

Can someone make sure that these kinematic equations I derived are accurate please? Thanks in advance. I'm new to this forum, so if I'm doing something wrong, let me know. I understand the below ...
0
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0answers
126 views

Do human body parts like hands or legs move with uniform acceleration?

So, is this true? I mean, does a movement by hand or leg make uniform or constant acceleration?
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2answers
110 views

Animating an Acceleration Vector - Acceleration of object on a crested path in gravitational field

So I was reading in Chapter 3 of my textbook, Sears & Zemanksky's University Physics with Modern Physics by Young and Freedman, 13th Edition, and the discussion took us to a definition of the ...
0
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4answers
297 views

Why don't we take force proportional to velocity? [duplicate]

When a Force is applied on a body at rest, it produces Acceleration which is equal to change in Velocity. But due to the Force, we see that the Velocity is increasing consequently. So why don't we ...
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3answers
289 views

What would happen if an unstoppable force hits an immovable object? [closed]

I realize that the question a rather large paradox, but I do wonder if such a thing were true what would happen, assuming that neither of these "objects" can be destroyed by each other?
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1answer
20 views

Acceleration of a container in thermodynamics

How will accelerating a container with an ideal gas in it affect the conditions? My initial thoughts are that the ideal gas will collect at the opposite end of acceleration, which means that the ...
1
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1answer
26 views

Question about central force,and acceleration of the tangent velocity due to a radial velocity and angular momentum conservation

I am a bit confused, and I'll appreciate some help. Let's say that a particle is moving under the influence of a central force. Let's say that its initial velocity, has both: tangent component and ...
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7answers
24k views

What does the magnitude of the acceleration mean?

I am a little confused as to what the magnitude of acceleration is and what it means.
2
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1answer
28 views

a problem on finding acceleration by differentiation

The displacement of particle along the $x$ and $y$ axis is \begin{cases} x(t)=\omega t-\sin\omega t\\ y(u)=1-\cos\omega t \end{cases} Upon differentiation, the velocity is \begin{cases} ...
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3answers
3k views

Does an Increase of Force affect the Speed of an object if the acceleration stays constant?

If I had a mass of $100\:\rm{kg}$ accelerating due to gravity, using $F=ma$: $F = 100\:\rm{kg} \times 9.8\:\rm{m/s^2}$ $F = 980 \:\rm N$... If I increased the mass to 200kg, the force would be 1960 ...
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0answers
16 views

Dynamics particle motion around ellipse [closed]

For particle motion at constant speed around an ellipse with a major axis of 4 inches and a minor axis of 2 inches the ratio of the acceleration at pt. A to B is?
4
votes
1answer
269 views

What happens in the twin paradox if the ship doesn't return?

What happens if the twin in the spaceship doesn't return? Would he still be younger than his other twin? Is the symmetry broken simply by accelerating out of earth? If it is still symmetrical when ...
0
votes
1answer
41 views

Are velocity and accelerate smooth quantities?

My thinking: acceleration corresponds to a force which is instantaneous, so the acceleration of a rigid body can be rather spiky (non-smooth) velocity (angular velocity) describes the ratio of ...
0
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2answers
32 views

How to find gravitational acceleration given $k$ in a power function

I have a problem that has been bugging me for a week, and I can't figure it out. We know the power function: $$ y=kx^n $$ I also have a set of data: I took the natural log of both of these data ...
1
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2answers
332 views

Does a heavy body move with the slightest force on a frictionless surface?

If I apply horizontal force on a body resting on the ground, my force will be opposed by the frictional force and the body will accelerate at the point where my force exceeds the force of friction = ...
1
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2answers
428 views

Gravity and free fall

In Wikipedia it's stated that "[..] gravity, is the natural phenomenon by which physical bodies appear to attract each other with a force proportional to their masses". Then I found many examples ...
0
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0answers
22 views

Motion of an electron in an Electric Field

I'm having trouble finding the acceleration of an electron which enters a constant electric field. What I know is that the velocity of the electron is $2.5 \times 10^6 \text{ m/s}$ with a mass of ...
0
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1answer
34 views

From escape velocity to gravitational acceleration

If all you are given is the escape velocity from the surface of Earth can you back calculate to Earths 9.8 m/s^2 gravitational acceleration? In the end what I am looking for is a formula with Escape ...
0
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0answers
15 views

Relation of gravitational pull with no air friction [duplicate]

I am confused between the gravitational pull and the air friction on the moon. Let me give you an example, I have learned that the greater the mass of the body the more gravitational force it ...
9
votes
3answers
572 views

How do we explain accelerated motion in Newtonian physics and in modern physics?

Maybe my question will seem stupid, but I am not a physicist so I have some problems understanding a classic Newtonian experiment: in the bucket experiment, why does he have to introduce the absolute ...
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1answer
50 views

Analytical Mechanics [closed]

This is one of my three homeworks. I see that $W_a(1) = \dot U_a(1)=\ddot{X_a}(1) = 0.3 $ Since $U_{O'}=0 $ then O' is Instant centre of rotation. Then $U_b = 2U_a = 0.6$ I tried a lot, about a ...
0
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2answers
68 views

Accelerometer validation trace

I am attempting to validate an accelerometer. I have a triaxial accelerometer and placed it on a wheel which goes at various frequencies from 1 to 3 Hz. Am I right in thinking that I would expect the ...
1
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1answer
65 views

Non-geodesic circular orbit? [closed]

From N. Straumann, General Relativity Exercise 4.9: Calculate the radial acceleration for a non-geodesic circular orbit in the Schwarzschild spacetime. Show that this becomes positive for ...
9
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2answers
2k views

Relativistic centripetal force

The thought randomly occurred to me that a circular particle accelerator would have to exert a lot of force in order to maintain the curvature of the trajectory. Many accelerators move particles at ...
0
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0answers
21 views

isolating centripedal acceleration

I have sensor that picks up both gravitational and centripetal acceleration, it also picks up tangential as it is in three axis. I guess if the sensor is put on a pendulum the tangential acceleration ...
0
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3answers
30 views

Do electrons get accelerated or decelerated by the atoms of the anode during X-rays production?

The electrons striking the anode get deflected by the heavy nucleus. Though the speed may or may not change, the direction of motion changes which leads to acceleration. The charged particles emit ...
2
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5answers
39k views

Finding the force of friction of a moving object and its change when it accelerates to a constant speed

I have been searching for a straight forward answer to this question for ages now and it is driving me crazy. Here is what I know: If an object is moving at a constant speed the force of friction ...
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0answers
39 views

Maxwell's Equations for Accelerated Conductors

I asked a question about accelerated conductors in a magnetic field but nobody unfortunately answered. That is: Ohm's Law for Accelerated Conductors Maybe, I could not state my question well. I ...
0
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2answers
77 views

How to use an accelerometer to correctly quantify the magnitude of vibrations

Consider the following setup, an accelerometer is placed inside a helicopter, measuring "g" values along 3 axes (x,y,z) every 10 ms (100 times a second), during a helicopter flight. If one, wants to ...
4
votes
3answers
93 views

Is acceleration caused by curvature or space or time or both?

I'm trying to get a hold of the idea of gravity in general relativity and spacetime. I've seen plenty of demonstrations of the rubber mat analogy to describe gravity and spacetime curvature. Is this ...
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2answers
305 views

Exact definition of momentarily comoving reference frame (MCRF)

Consider a particle $P$ in the framework of special relativity with position $r(t)=(ct,x(t),y(t),z(t))$ respect to an inertial reference frame $\Sigma=(ct,x,y,z;O)$. I need to know if the following ...
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4answers
228 views

Why does objects with zero acceleraton move?

My question is, if we apply a force on an object to move it with a constant velocity, of course it will move. But what I don't understand is, why will it move? From Newton's law F=ma and in this case ...
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1answer
27 views

Finding acceleration only with known acceleration distance, final velocity, and mass for Newton's Third Law [closed]

So I have this problem that I am trying to figure out. I need to find the acceleration of a 4 kg object, that is accelerated through a distance of 1 m to the left to a final velocity of 6 m/s. This ...
0
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2answers
303 views

How does artificial gravity reduction (weightlessness) work on Earth?

Some of us have been to those amusement park/carnival/theme park rides where you enter some capsule/machine, and you will float, etc. There is also some other thing where you go inside a big room ...
5
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1answer
116 views

Explanation for “if all accelerated systems are equivalent, then Euclidean geometry cannot hold in all of them”

I'm doing an EPQ (mini college research paper) on gravity, and I found a site that explained things in simple terms. I am having trouble understanding how Einstein came to his revelation space-time ...
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5answers
5k views

How fast would someone have to run to travel vertically up a wall?

I am currently doing a physics project on the effects of so-called 'super-speed'. I was wondering how fast you would have to run to vertically travel up a wall? That is, to negate the force of ...
0
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4answers
75 views

How is acceleration measured if there is change only in the direction of velocity & not magnitude?

The formal definition of acceleration is It is the measure of how fast the velocity changes with respect to time. Now, when the magnitude of velocity changes, acceleration $$\vec{a} = \frac{d ...
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3answers
6k views

Why does a parachute decrease terminal velocity?

Terminal Velocity depends on two things- surface area and speed. These are inversely proportionate. If both these variables affect terminal velocity, why do parachutes slow you down? Initially you ...
1
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1answer
35 views

What matters more in the strength tester game at a carnival, momentum or force?

A buddy and I were arguing over which matters more in the strength tester game (assuming the same accuracy of the hit): 1) momentum or 2) force. He was arguing that if you swing the hammer directly ...
2
votes
1answer
46 views

Rate of acceleration for two hanging masses in two experiments

I conducted an experiment where two masses of different weight were attached by a string and fed through a pulley. The difference between the masses was $0.025\: \mathrm{kg}$. The lighter mass was ...
3
votes
5answers
408 views

Help understanding Bell's Spaceship paradox

The problem statement of Bell's Spaceship paradox is this: Two spaceships float in space and are at rest relative to each other. They are connected by a string. The string is strong, but it ...
0
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1answer
33 views

Finding acceleration and distance when velocity given

I am trying to do the following question for practice (it is an interview question), and I don't know if my methods and answer are correct. Given a velocity $v=2+3t^2$, find acceleration after 3 ...
2
votes
1answer
105 views

The 3rd derivative of the size of the universe?

We know the size of observable universe, that it is expanding, that expansion is accelerating. Does sufficiently precise data exist to determine at least the SIGN of the next (the 3rd) derivative? ...
0
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0answers
59 views

Is the gravitational acceleration at the event horizon constant?

If the escape velocity at the event horizon of a black hole is equal to the speed of light, does this imply that the gravitational acceleration at the event horizon is also constant? For example, ...
3
votes
1answer
38 views

Burning fuel in space while accelerating and deaccelerating

Is it true that for acceleration in space we need not the same quantity of the fuel than during the deacceleration stage?
0
votes
1answer
64 views

Finding Acceleration of Two Masses in an Ideal Pulley [closed]

I am stuck on this problem: Two masses are connected by a string which goes over an ideal pulley. Block A has a mass of 5kg and can slide along a rough plane inclined 30 degrees to the horizontal. ...
4
votes
2answers
323 views

Potential energy conservation in traversable wormholes

Let's say I have a tube, of large radius (about 5 - 7 meters in diameter), with traversable wormholes at the ends. The wormholes are arranged as such that if something falls inside one hole from ...
6
votes
3answers
115 views

How to describe arbitrary accelerations in special relativity

Describing acceleration in special relativity is in principle straightforward, and for simple cases the resulting transformations are simple. Examples include circular motion and constant acceleration ...