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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Rolling (without slipping) ball on a moving surface 2 [duplicate]
Possible Duplicate:
Rolling (without slipping) ball on a moving surface
Apparently I didn't log in properly when I asked a question this morning: Rolling (without slipping) ball on a moving ...
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Rolling (without slipping) ball on a moving surface
I've been looking at examples of a ball rolling without slipping down an inclined surface. What happens if the incline angle changes as the ball is rolling?
More precisely I've been trying to find ...
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How can kinetic energy be proportional to the square of velocity, when velocity is relative?
Let's start with kinetic energy (from los Wikipedias)
The kinetic energy of an object is the energy which it possesses due to its motion. It is defined as the work needed to accelerate a body of a ...
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Moon and the moving train
While travelling by train (travelling West to East), it seems the moon is moving in opposite direction when seen from the window, but then it reverses its direction, after a certain amount of time and ...
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What direction a flag on an object moving in the wind shows?
"The flag of a ship that is moving northward with 10 km/h, points exactly southwestward. The windsock at the lighthouse points under 30 relative to the western direction southward. Calculate the ...
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Galilean relativity in projectile motion
Consider a reference frame $S^'$ moving in the initial direction of motion of a projectile launched at time, $t=0$. In the frame $S$ the projectile motion is:
$$x=u(cos\theta)t$$
$$y=u(sin\theta)t-\...
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Riddle: can you swim faster upstream than downstream (with respect to the water)? [closed]
A friend of mine posed a riddle to me:
A man swims upstream in a river, which is flowing at an unknown rate. He is wearing swimming goggles. At a certain point he loses his goggles. 10 minutes later ...
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Measure absolute speed
Currently I'm 17 years old, going to secondary school. So, my ideas might be totally wrong...
I know that everything is relative. In the example of speed, the earth moves, and the galaxy moves, etc.
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Waves travelling with water flow
Suppose I use a tool to create a circular wave in the river. If there are two fish swimming 1m from the source (2m from one another), they will both feel the wave at the same time.
What will happen ...
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Calculating velocities using Reference frames
Suppose an object A is traveling at a velocity of 100 m/s, and another object B is traveling at 105 m/s. With both the objects traveling through the same direction, taking A as a reference frame, the ...
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Galileo's dictum and how light cannot violate it
Okay. So I've been told that the speed of light is constant and cannot violate Galileo's dictum, but even if it weren't constant (in a vacuum), how would it violate it anyway?
Say you are on a train ...
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Space Expansion vs. Relative Motion
Given 2 objects moving at some velocity $v$ relative to one another, is it possible to determine whether they are moving or whether the space between them is expanding?
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How will you measure speed in km/hr in space?
How is the speed of an object in space measured? Also more importantly how do you measure your own speed in space? On the road we use a speedometer which tells us the speed easily. How is it done in ...
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Relative Speed vs speed of light [duplicate]
Possible Duplicate:
Travelling faster than the speed of light
Someting almost faster than light traveling on something else almost faster than light
I've got two questions which are related and ...
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Does an airplane's speed include the speed of the Earth?
After take off, does airplane's speed include Earth's movement/speed? Do airplanes turn with Earth movement/rotation?
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