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Questions tagged [speed]

Scalar quantity which is the magnitude of velocity.

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True Airspeed from Indicated Airspeed, Temperature, and Altitude

I'm working on an aircraft problem to figure out the true heading we need to fly in order to end up where we want with the presence of wind, and I think I have the whole thing figured out except for ...
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Scale diagram confusion

I’m familiar with scale diagrams where three forces act upon an object and trigonometry is used to find the resultant force, but I’ve come across questions that use units of velocity instead of force. ...
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What is the rate of change of speed called? [duplicate]

Magnitude of acceleration is definitely not the answer in case of rate of change of speed unless it it is moving in a straight path. So is there any name for rate of change of speed?
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Is there centripetal acceleration with velocity of 5 m/s?

So if an object is moving at $5\ \mathrm{m\ s^{-1}}$ in a circle, is it accelerating? Me and a friend are having a conversation about this.
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Relation of Speed in Circular Motion [duplicate]

At what velocity does a car skid or slip on a circular road with radius R and friction coefficient u.
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How does different shuffleboard powder affect the disks' speed

I do know there is friction and surface tension involved here but am not sure on how exactly does different kinds of shuffleboard powder affect the disks' speed. So taking into the account the ...
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2answers
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Speed and tangential acceleration in pendulum motion

Speed is a scalar quantity which corresponds to the magnitude of velocity, so it must always be nonnegative. In a general 2d motion, the tangential component of acceleration is given by the time ...
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Would not the oscillation of light slow down the wave? [duplicate]

Would not the oscillation of the light wave slow down the wave? Does light travel at "c" of its net position over time, or does it travel at "c" on the wave?
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Meaning of REALLY Slow Speeds

So we have a fairly good grasp of how entities behave at extremely fast speeds (visa vi relativity etc) but what about incredibly slow speeds? I’m a Physics student and we were covering Broglie waves....
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How is vectorial Doppler computed when both transmitter and receiver are moving?

In a technical document, I have found the following formula for the Doppler of two moving devices: $d=\frac{\bar{r}_{rx}^T\cdot \bar{v}_{rx}+\bar{r}_{tx}^T\cdot \bar{v}_{tx}+2\cdot \alpha\cdot D}{\...
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1answer
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Does Horizontal Velocity remain constant when it hits a surface in a Parabolic Motion?

It is told in one of the answers that the horizontal velocity stays at 4.0 m/s after the ball bounces from the plate. Why is it still at 4.0m/s, isn't there friction or is it neglected for the sake ...
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If a black hole is created from light, can this black hole then move at the speed of light?

Imagine we managed to squeeze light into a very tiny region of space so that the energy concentration at that point becomes a black hole. Can this black hole then move at the speed of light?
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What is the best way to conceptualise a 'division' [closed]

This may seem like a strange question, but my question is more along the lines of trying to figure out how people were able to 'discover' the formulas which have shaped our understanding of the ...
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How to express the Earth's orbital speed as a function of time?

I would like to create a function that tells me the orbital speed of Earth at any given day. The vis-viva equation says that v=√(GM(2/r-1/a) ), expressing speed as a function of distance from the ...
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If you were to push a block in space in an ideal vacuum scenario with zero friction, what would be the final velocity of that object

Say you push an object with 10 N force(just once and let it go) of mass 10kg object in space with zero friction and nothing in the way of its path. What would be the velocity of that object? I would ...
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Calculate speed of an object using angle and time [closed]

I haven't had any physics class or anything close to that in a long time, and I'm currently confronted with an exercise I don't remember the formula(s) to solve it. Assuming I have an object of ...
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Is it speed or acceleration that leads to time dilation? [duplicate]

Is it acceleration or speed that leads to time dilation or both? For example, when a spaceship accelerated to (almost) the speed of light, then reversed course to come back towards earth, does this ...
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Can a projectile bullet kill? [closed]

Today, I was watching a movie, in which a person shot a gun in air. The bullet went high in sky, became stationary for a moment and dived back and killing a non-innocent person by hitting him in head ...
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Spiral lamp chane state speed [closed]

Question is how fast halogen lamp reach it full temperature, going from cold (not light) state to full light emit state. how fast in milliseconds it takes, imagine: if led lamp work instantly like 0 ...
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Why does a car's steering wheel get lighter with increasing speed [closed]

I've noticed it is difficult to turn the wheels of a car when the car is stationary, especially cars without power steering, which is why the power steering was invented. However, I've noticed it ...
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2answers
28 views

Confusion on Horizontal & Vertical Components of a Parabolic Motion

This was a question I found about projectile motion, the question was what's the bike's speed when it took off. Using $S=ut + 0.5at^2$, the time taken to reach the ground is $0.505 s$, they used ...
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1answer
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Why $g$ on equator is less than $g$ on poles? [duplicate]

I found this on my physics book. The book says $g$ on equator 9.78 $m/s^2$ and on the poles 9.81 $m/s^2$. Is it due to gravity?
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What is the difference between velocity and speed? [duplicate]

What is the difference between velocity and speed? could anyone describe it more specific? does velocity have direction?
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33 views

Does the weight on a car's wheels decrease with increasing speeds? [duplicate]

Ignoring the reduction in fuel weight as it burns, does the weight on a car's wheels decrease with increasing speeds? If so, by how much and is there a fomula for calculating that? At what speeds ...
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28 views

Two containers that have the same volume (let say 500 liter) but are different in shape

I remember from school, one time a teacher explain us the following: two containers of the same volume, but one is thin and tall, and the second is short and wide. then if we fill them with water from ...
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Would a human age faster if these certain conditions are met?

So, a human would travel in a rocket in outer space. There is little to no gravity, and the pressure may or may not have an affect (?) on what i'm about to ask. It has been proven that when a human ...
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Why is a particle non-relativistic when its kinetic energy is small compared to its rest energy?

For example, nucleons in nucleus are in motion with kinetic energies of 10 MeV. Their rest energies are about 1000 MeV. Kinetic energy of nucleons is small compared to rest energy. They are hence ...
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104 views

Calculation of speed from accelerometer data

I am trying to use my accelerometer on my mobile device fitness band to find the speed of walking and running. I conducted my experiment of walking and running on treadmill where I asked a person to ...
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3answers
58 views

Effect on speed when decreasing the magnitude of acceleration

I'm struggling to come up with an answer to the following situation and question: "Suppose you are driving your car along a straight road in the positive direction and are speeding up (increasing ...
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2answers
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What would the position vs. time graph look like if the velocity vs. time graph was a curve?

In my physics class we are learning about velocity vs. time graphs and position vs. time graphs for an object. We have learned that if the object is moving with constant velocity (this would be a ...
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61 views

How does the increase of heat increases the speed of a particle?

I am fairly new to the thermodynamics topic, I have been introduced that as the temperature of a particle increases, so does the speed of the particle; it moves faster. However, I never been told how ...
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Does multiple tensioning pulley affects the belt speed?

Consider a multiple pulley system with the main pulley(30mm) attached to the motor shaft and multiple tensioning pulley in different locations(all are 15mm), driven pulley of 15mm is connected to the ...
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Where does this equation come from?

I am investigating about viscosity of fluids and I found the following equation to calculate the viscosity: $$\nu = \frac{2(\rho_s-\rho_l)\cdot g \cdot r^{2}}{9\cdot\Delta v} $$ The experiment ...
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Sound and gravity

How would heavier gravity (or lighter gravity) affect sound in terms of what I hear? For example, say there is a planet that is capable of supporting human life, but it has heavier gravity than ...
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153 views

Why is escape velocity independent of direction of projection?

However, for any body projected with a velocity less then the escape velocity, the final maximum height will vary with variation in angle of projection. But why is this not the case in case of ...
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2answers
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Why is $\sqrt{gR}=v$ same for finding Minimum and Maximum Speed?

I was wondering this: Why is the $\sqrt{gR}=v$ the same for finding minimum speed and maximum speed? Like if you are wondering the min. velocity for keeping a rollercoaster on track when on top of the ...
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158 views

What causes the wave velocity of longitudinal waves in a spring to changes as its length changes?

This video shows the velocity of longitudinal waves changing in a slinky spring as its length changes: https://youtu.be/y7qS6SyyrFU?t=17 Something else responsible for the change in velocity ...
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A question on the properties of wave equations

When you change $$y(x,t)=A\sin(kx-ωt+φ) $$ into $$y(x,t)=A\sin(2kx-2ωt+φ), $$ does it double the wavelength because $k$ changes into $2k$ and double the frequency since ω is doubled? If this is ...
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Is one side of earth faster at night and slower at daytime?

I'm reading Physics for Entertainment by Yakov Perelman and in it he says under "When we move around the sun faster" that at midnight the speed of the rotation of the earth is added to that of earth's ...
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“Speed” of gravity? [duplicate]

This is probably going to be a poorly written question, since I know really a little of physics. Imagine a object of small mass, let's say a book, is floating in the universe in absence of any ...
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What is the interpretation of speed of a travelling wave, based on $\frac {\partial x}{\partial t}$ formula

Motion satisfies the wave equation if the following holds true $$\nu^2 * \frac {\partial ^2 \psi} {\partial x^2} = \frac {\partial ^2\psi} {\partial t^2}$$ where $\psi$ is the vertical displacement ...
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What is the speed of the magnetic field?

There is an invisible magnetic field that pushes apart two repelling magnets What is the speed of that magnetic field?
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Interesting speed of sound observation

I just came by a table in the Class 11 Physics NCERT textbook, listing speeds of sound in different media. Vulcanised rubber has an unusually low speed of sound $54\ \mathrm{m}/\mathrm{s}$ as compared ...
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3answers
238 views

What would be the minimum velocity of a particle performing S.H.M.?

We were asked a simple question on a test: What is the maximum and minimum velocity of a particle performing an SHM? Note here that we're talking about a generic standard SHM here. If the maximum ...
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3answers
173 views

What is the speed of a photon in water?

What is the speed of light in water? The speed of light in vacuum, divided by the index of refraction for water. And what is the speed of a photon in water?
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1answer
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Are my observations about the differences between average velocity and speed, in 1 dimension, correct?

I've been struggling to understand the differences between average velocity and average speed in 1 dimension; by doing some exercises I think I have figured it out, but i want to check if I'm correct. ...
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Would a supersonic object without a combustion power source leave behind a contrail?

Contrails, as far as I understand them, are caused by either a pressure change that forces the condensation of H2O(g) OR by the release of warm H2O from a combustion engine. Most plane contrails, I ...
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216 views

Rolling objects released from rest: time down the ramp [closed]

Since we are given the values of I for each object, I was able to calculate the KE's of each: the solid spheres had KE of $1/5mv^2$; the hollow sphere had a KE of $1/5 mv^2$, and the hoop had $1/2mv^2$...
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Speed and frequency of a transverse wave traveling through a string made of different materials [closed]

Say a wave generated by an oscillation machine is traveling through a string. Will the frequency of the wave be the same across the string if: The string is made up of 2 different materials with the ...
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61 views

Speed of solar system through dark matter halo

How is the speed of the solar system through the dark matter halo determined? Direct dark matter detection experiments rely on this speed estimate. Assuming the sun/earth travel through the dark ...