Questions tagged [relative-motion]
Use this tag for questions related to how objects move relative to other objects dependent on your frame of reference, and how this applies to special relativity.
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Why is direction of train like this for car?
This is an image of a train and a car. T is the train moving towards - $x$ axis and C is the car moving towards $+ y$axis.
So, my teacher made a resultant velocity with $-5\hat i$ and $-20\hat j$. ...
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Is this correct regarding velocity of train?
So many yellow T drawn are just different position of train at different instants.The person is standing still at all those instants at one place.
If a train is moving at 5m/s.
Then for me , can we ...
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Direction of $V_RM$ confusion
So ,please read both the questions . They have similar originate questions that I am facing difficult in.
Let us say rain is falling downwards with v = -5j and a man is moving with a velocity of 2i in ...
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Discretizing kinematics of moving object
I think this is a simple question, but I'm unable to find the relationship:
The relative distance between two objects at any time $t$ can be written as:
$x_r(t)=x_{ro}+\int_{t_0}^{t_f}v_r(t)dt$
where:
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What do you think of the idea of measuring macroscopic Special Relativistic-kinematic time dilation by placing atomic clocks onto moving dollies?
We first attempt to synchronize two stationary clocks placed apart, and we assume we succeed using the Einstein synchronization convention.
Then, we run a third clock along a dolly at a constant speed....
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Relative speed of satellites in different orbits [closed]
The question is
"The Hubble Space Telescope is in orbit around the Earth at a height of 560km above the Earth’s surface. Take the radius and mass of the Earth to be 6.4×10^ 6m and 6.0×10^24 kg, ...
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Is this an exception to Newton's Second Law of Motion?
If a ball in an experiment is dropped from two different heights, 6 feet and 12 feet, why would we need to exert more force when we catch the ball that is dropped from the height of 12 feet? According ...
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Why is relative motion at constant velocity the same as being at rest?
If I am a passenger who plays catching-the-ball game inside a vehicle that moves with a constant velocity in a straight road, why can I catch the ball repeatedly that as if the vehicle is at rest? How ...
user282164
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Not able to understand relative velocity in 2dimension?
I have a body A = 4j and B = -3i
Their relative velocity = -3i-4j.
But the position is somewhere they both don’t even meet.
It should be from B to A but it form C to A or B.Not able to understand what ...
user280997
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How does the orbital motion of reduced mass tell us how the individual planets/stars move?
To give context to my question, here is Kepler's first Law restated in terms of reduced mass. Here, $\vec{r}$ is the position vector of the reduced mass whose origin lies at the centre of mass of the ...
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I want to know the difference in two methods I have solved [closed]
A thief is driving away on a straight road in jeep moving with a speed of 9 m/s. A police man chases him on a motorcycle moving at a speed of 10 m/s. If the instantaneous separation of the jeep from ...
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Time dilatation - relative movement
Sorry for eventual factual errors, I am just hobbyist.
A spaceship flies with nearly speed of light away from earth and back.
Time on board were going slower than on earth during flight, so back on ...
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Does the magnitude of heat energy given or taken the same in any reference frame
So the question consists of two parts-
The random motion of the particles is equivalent the amount of heat energy. The velocity of collective motion does not result in heat energy. For example take ...
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Simple Harmonic Motion example [closed]
https://en.wikipedia.org/wiki/Escalator
https://en.wikipedia.org/wiki/Simple_harmonic_motion
Can we classify escalator device as a Simple Harmonic motion example?
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What really pushes a rocket up?
To launch a rocket, fuel is burnt and is released in opposite direction relative to rocket and it pushes the rocket upwards because of third law of motion but the fuel molecules are not actually ...
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How does motional EMF emerge from Jefimenko's Equations?
I have been using Jefimenko's Equations for determining the electric and magnetic fields of a conductive coil with a (possibly changing) current. For most situations of interest this can be done to ...
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Coriolis force and liquid on a rotating space station?
On a rotating wheel space station crewed by humans with sea-level conditions (temperature above the freezing point), if liquid was spilled on the floor am I correct in understanding that the Coriolis ...
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Can we prove the Earth rotation with a disk mounted in its center on a frictionless axis?
Can somebody prove the rotation of Earth if it places an uniform disk with a hole in its the center on an axis and orient it paralelly to Sun ecliptical disk?Just assure himself that the disk on the ...
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A question about Lorentz force
According to standard electromagnetic theory, if the charge A is stationary and the charge B is moving along arbitrary trajectory then the electromagnetic force on charge A is:
$$\vec{F}_A = q_A \left(...
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Swing in moving truck
I was just thinking about a situation in which a big truck is moving in high speed say ( $80 \ miles/hr$). There is a swing attached with the ceiling of the truck container which can move freely in ...
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Calculating unknown Relative Velocity from Given 2 Known Relative Velocities for speeds comparable to speed of Light
Dear fellow physics lovers,
Given 3 objects A, B and C, travelling with relative velocities such that
$\vec{v_{AB}}$ = Velocity of Object A with respect to Object B
$\vec{v_{BC}}$ = Velocity of Object ...
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Kinematics in moving reference frames
Assume we have an object moving along a path $p_W(t)$ that is described in some fixed reference frame $W$. If we now have a second reference frame $B$ which differs from $W$ by some time varying ...
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Why does the relative motion go wrong here?
Question statement:
A rocket is moving in a gravity free space with a constant acceleration of 2ms−2, along + x direction (see figure). The length of a chamber inside the rocket is 4 m. A ball is ...
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Doesn't this experiment signify that inertial frames are not equivalent? [duplicate]
When we talk about kinetic energy of a body, it is actually the combined kinetic energies of all the atoms in that body. Now suppose a body is at rest. So its atoms would have some internal random ...
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Relative Motion in Two Dimensions
There's a problem that I've been working on in physics for a couple of days now, and I'm just wondering if my thinking is wrong here. Say you're given the velocity of an object (with an x- and y-...
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Relativistic or non relativiistic mechanics?
Question: A train of length $l=350 metres$ starts moving rectilinearly with the constant acceleration $a=3×10^-² ms^-²$; $t=30s$ after the start the locomotive headlight is switched on $(event 1)$, ...
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Motion of Points around a Triangle [closed]
I came across this problem in the book "Problems in General Physics by IE Irodov"-
Three points are located at the vertices of an equilateral triangle whose side equals s. They all start ...
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Velocity Question from grandparent
My Grandparent asked me this question a few years ago, and I am getting around to giving him an answer, but I don't know the answer. Can anyone help?
"A pickup truck is speeding along a highway ...
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Coriolis effect vs preservation of angular momentum on merry-go-round, sniper's bullet, hovering helicopter and high altitude rockets
I understand that how helicopter hovers at the same position or a thrown ball falls to the same position even though earth is spinning. This is due to the preservation of angular momentum and my ...
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Why motion is not absolute or relative to space? [closed]
We say that motion isn't absolute.but why?if we measure motion relative to "space" it will be absolute for all observers. isn't it?
Is space also relative like motion?
If space has no "...
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Is the frame of elevator Preferred over the frame of ground? [closed]
When an object is thrown upward with some velocity then it doesn't fall towards the earth until the given velocity becomes zero.
Now imagine the case given in the figure
There is a question in my ...
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How to decide which velocity is bigger in a collision before writing velocity of approach and velocity of separation?
My teacher said that velocity of separation is $V_1$- $V_2$ where $V_1$ is greater than $V_2$ and said same for velocity of approach. The problem is how would you determine which velocity is greater ...
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Relative angular velocity of one point with respect to another on a solid rigid body [closed]
What is relative angular velocity of A wrt B and that of A wrt C in the figure given below?
Description:
A, B and C lie on a solid cylinder(rigid body) rotating with a constant angular velocity $\vec{...
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Flying a drone in a moving car/airplane
Why does a drone fly with respect to the air in a moving car/airplane, but not in an elevator as shown in this clip: What Happens If You Fly a Drone In An Elevator?
I understand that the drone will ...
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Magnitude of relative velocity between two frames in special relativity
It seems to be taken trivially, and it is indeed intuitive, that the relative velocity $v$ of some frame $O$ with respect to $O'$ is the same in magnitude to the relative velocity of $O'$ with respect ...
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Relative speed of galaxies in deep space
Let say we observe two galaxies, one little bit closer to us than the other one. If we calculate the speed of the farther one does it mean that according to the Hubble law when the closer one reaches ...
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Does Relativity make a difference on whether Earth revolves around the Sun or not?
According to the theory of relativity there is no ultimate preferred frame of reference in our universe. It means that whenever there is motion between object A and object B, whether it is considered ...
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How can different points on a rigid body move with different speeds but also be relatively at rest?
For a rigid body rotating with a constant angular speed, the points near the axis must have lower linear velocity than the points farther away. If they have different linear velocities, they must have ...
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Why is the following equation not correct? [closed]
Q)Point A moves uniformly with velocity $v$ so that the vector $v$ is continually "aimed" at point B which in its turn moves rectilinearly and uniformly with velocity $u<v$. At the ...
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Relative Velocity of two particles [closed]
If two particle are neither approaching towards nor receding away from other then their relative velocity is non zero.
How is this possible??
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Change in Kinetic Energy in two different reference frames (one of them non-inertial) [duplicate]
Let's say an object of mass 10 kg is fired from a cart of mass 90 kg. The object and the cart, of total mass 100 kg were initially moving together with a speed of 10 m/s. Then, the object is fired by ...
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Magnetic field and frame of reference [closed]
A charged particle moves with a velocity near a wire carrying an electric current,and suppose I see the particle from a frame moving with same velocity in the same direction . I will see the charge at ...
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Does a magnetic field (moving relative to the charge) act on a stationary charge? [duplicate]
Does a magnetic field moving relative to a stationary charge act on it?
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Why distance between 2 particles is independent of frame?
I was solving question in kinematics related to minimum distance between particles there they said that distance between two particles is independent of frame the distance they both measure between ...
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Spinning observer inside a solenoid paradox?
It is well known that magnetic fields are frame dependent, with an observer travelling parallel to a moving point charge experiencing no field.
Similarly for a solenoid, a stationary observer on the ...
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Do the time taken to travel a fixed distance changes in two different inertial frame of reference in relative motion
I have calculated time taken to travel a fixed distance by the object from two different frames of refrence. One frame was moving with uniform velocity wrt other . But time taken to cover the equal ...
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Why is heat energy dissipation in two intervals frame dependent?
The question asks for heat produced in the given specific conditions. It seems like an application of the work-energy theorem with friction doing work on the block and dissipating the heat in the ...
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Why don't hovercrafts move West relative to the Earth [duplicate]
Suppose that there is a hovercraft floating a few centimetres above the Earth's surface. As it is disconnected from the Earth, which is spinning from West to East, shouldn't it appear to move East to ...
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Upstream and downstream problem using relative velocity
On a river coast, there is a port; when a barge passed the port, a motor boat departed from the port to a village at the distance $S_1 = 15$ km downstream. It reached its destination after $t = 45$ ...
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Who applies the force on the things moving backward that we see when moving forward? [duplicate]
When we move forward in a car, things around us move backward. I understand some force is being applied on the car that is the reason for its forward movement. But what is the source of force on the ...
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