Relative Definition and 1000 Threads

Einstein made the theory based on Maxwell saying that electromagnetic waves travel with same speed from the view of all inertial & non - inertial frame. Then with what speed relative to a person sitting on light does light travel ?

Homework Statement A stone is dropped from a balloon at an altitude of 300 metres. How much time is required for the stone to reach Earth if: (1) Balloon is ascending with a velocity of 5 m/s, (2) Balloon is descending with a velocity of 5 m/s (3) Balloon is stationary Disregard air...

Homework Statement A ship goes from A to B at v_1=10 km/h and from B to A at v_2=16 km/h Find: (1) the average velocity of the ship, and (2) the velocity of the river current. Homework Equations v_{avg}=(v_1+v_2)/2 v_{AC}=v_{AB}+v_{BC} The Attempt at a Solution...

A light plane is headed due south with a speed relative to still air of 185 km/h. After 1 h, the pilot notices that they have covered only 135 km and their direction is not south but 75˚ south of east. What is the wind velocity? I know I have to set up a triangle and solve...

Homework Statement A canoe has a velocity of 0.360m/s southeast (at 315°) relative to the earth. The canoe is on a river that is flowing at 0.580m/s east relative to the earth. Find the magnitude of the velocity v⃗ c/r of the canoe relative to the river. Homework Equations...

Okay guys, I still feel like I don't quite understand these concepts well enough. Do you guys have any websites or links to help me understand these concepts better? I feel like I only partially understand these concepts. I also feel like I partially understand the application of the mathematics...

Homework Statement The last stage of a rocket, which is traveling at a speed of 7600m/s, consists of two parts that are clamped together: a rocket case with a mass of 290.0 kg and a payload capsule with a mass of 150.0kg. When the clamp is released, a compressed spring causes the two parts to...

Q: The pilot of an aircraft flies due east relative to the ground in a wind blowing 20 km/h toward the south. If the speed of the aircraft in the absence of wind is 70 km/h, what is the speed of the aircraft relative to the ground? I set up the vector of wind WRT ground pointing due south...

Hello Is there any way that RH over water in a closed container could not be 100%? Assuming that the walls of the container are at the same temperature as the contents, that sufficient time has gone by for uniform diffusion of water vapour, that we are at usual room temperatures and...

Hi, I have my GSCE in maths but since then have not been that involved with it. Recently I've got very interested in probabilities, statistics with particular reference to modelling tennis match outcomes. I'm struggling to break down and understand the below and what I'd like to do is...

Here's a weird question where I don't quite know if length contraction or time dilation play a role. Say I have 2 spaceships moving towards each other. rest length of spaceship A is La and spaceship B is Lb. The pilot in A determines that time taken for the spaceship B to traverse the length...

Homework Statement The problem is worded thus: You are on an airplane traveling 30° south of due west at 130 m/s with respect to the air. The air is moving with a speed 30 m/s with respect to the ground due north. (a) What is the speed of the plane with respect to the...

Frictional force opposes relative motion and not just motion. Can you please give an example to further explain this statement? :confused:

why do we keep the sun to be the reference point and study the solar system and universe relative to it and why not relative to the Earth?

A simple experiment can be build to demonstrate a possible contradiction between thinking theory and reality. Use two hand electrical light torches set upon a table and back to back. Switch them on simultaneously, and calculate the relative velocity of their opposite leaving flashes...

Homework Statement A room with volume 2000 cubic metres has air at T=25degrees Celsius with relative humidity 80%. Density of water vapor in saturated air at 25deg Celsius is 22.8g/m^3. Temperature and pressure of room remains constant. What mass of water vapor must be removed from this air to...

Homework Statement A canoeist wants to travel straight across a river that is 0.10km wide. However, there is a strong current moving downstream with a velocity of 3.0km/h. The canoeist can maintain a velocity relative to the water of 4.0km/h. a) In what direction should the canoeist...

Homework Statement Solved Homework Equations The Attempt at a Solution Solved

The swimmer will move in the direction of resultant of his velocity and velocity of water. Draw the diagram and the try to solve it.

Homework Statement A tube (both ends open, height h, diameter d) is immersed into water so that length h1 of the tube is above water. Then the top of the tube is covered tightly and the tube is pulled out of the water so that length h2 is above water. The relative humidity of air is \phi and...

Hi all, I was thinking about special relativity and spacetime and had the thought of measuring our velocity with respect to spacetime. I was wondering why this would't work and what makes it different from the ether, which we would be able to measure our velocity with repsect to to determine...

Can anyone help me with the below? Air is drawn into a compressor at normal temperature and pressure (N.T.P) and compressed to a pressure of 6 bar gauge. After compression the air is delivered at 1.2 m3 min-1 and cooled to a temperature of 30°C, at which point condensate is collected at the...

If velocity is relative and if we cannot say which is moving away from what *objectivley, how do we say that time dilation is relative as well if we can tell who experienced the time dilation, as special relativity shows - and other experiments (muon concentrations etc). For example the jets...

HElp With Problem 1 see image Ahora In THIS problem Part 1 without wind I understand it perfectly But where are the 10 km and 20 km come from? y b) Why do arcsin ( 40/220)?

According to my understanding of SR, a light photon traveling at c, of course, relative to me "experiences" no time. In other words, it is not traveling through, at least, the time dimension I am traveling through. A neutrino, say, moving close to c does, but it is traveling very slowly...

So when looking at a hysteresis loop, the x-axis is the magnitude of H-field, and the y-axis is the magnitude of B-field. H is in units of electricity and B is in units of magnetic flux density. My question relates to how coercivity is determined if the material being magnetized has a...

Homework Statement I know that if you have 2 observers, "A", one at rest and the other "B" moving wrt "A" and if the moving observer shoots a projectile, then we can calculate the velocity of the projectile wrt "A" using the standard equation shown below. I was thinking what equation would...

If the axis of the Earth is tilted at 23.4 degrees away from the North Ecliptic Pole, and the Ecliptic Plane is tilted at 60.2 degrees away from the North Galactic Pole, then why is the Earth's rotational axis inclined at 27.13 degrees relative to the Galactic Equator instead of (90-(60.2+23.4))...

The title was too long, original question was: Why is the relative biological effectiveness (RBE) of photon and electron the same ? I was suspecting the charge of electron to possibly have some effect... Also, in biological matter, would there be a difference between photon damage and...

Homework Statement Calculate the relative uncertainty in the mass mass (M) = 1.0 grams Homework Equations \frac{\delta M}{M} The Attempt at a Solution \delta M = \pm0.05g \frac {0.05g}{1.0g} = 0.05 or \frac {0.05g}{1.0g} = 0.050 Which one has the appropriate amount of sig figs? thanks...

I'm running a simulation on a gas mixture that spits out its Specific Heat in a number of different units. The values for Specific Heat in Btu/lbmolF vs Btu/lbmolR are the same, which confuses me at first glance. I sort of remember in Thermo not having to worry about Btu/lbmolF vs...

A flat rectangular barge,48m long and 20m wide, is headed directly across a stream at 4.5 km/h. The stream flows at 3.8 km/h. What is the Velocity, relative to the riverbed, of a person walking diagonally across the barge at 5km/h while facing the opposite upstream bank? Hi Guys, having some...

Please Solve this problem Book answer The velocity components are x = 0.50 m/s y = (0.40 m/s)/sqrt (2) east and (0.40 m/s)/sqrt (2) south, for a velocity relative to the Earth of 0.36 m/s, 52.5 south of west. Ok I think these components are of an angle of 45 º but whwn i Calculate from...

To each other? Repondez!

Homework Statement A spaceship travels from Earth to the vicinity of the star that is measured by astronomers on Earth to be six light-years away. The spaceship and its occupants have a total rest mass of 32 000 kg. Assume that the spaceship travels at constant velocity. The time taken as...

Hello. So I always hear people say, "If someone flew in a ship at light speed to a far away star and then came back to earth, and it only took him two years to travel (the star being a light year away). When he came back all of his family/friends would have been dead for a long time." My...

Homework Statement Mary sits on the perimeter of a merry-go-round undergoing uniform circular motion. Matt stands on the ground 12 m from the centre of the merry-go-round. Matt observes Mary coming towards him at a speed of 1 m/s. What is Matt's speed from the point of view of Mary? (Ans...

Homework Statement Two clocks located at the origins of the K and K' systems (which have a relative speed v) are synchronized when the origins coincide. After a time t, an observer at the origin of the K system observes the K' clock by means of a telescope. What time does the K' clock...

Homework Statement The Earth is slightly thicker around the equator and hence $I_{0}\neq I_{\zeta}$ I am curious in finding the angular velocity for the **precession** between using the fact that the distance between the spin axis and the precession axis is 10 meters on the surface of earth...

if we know the relations between time and distance at the moving frame and stationary frame why can't we derive the velocity in the moving frame in a such way. Please point out my mistake. See attachment.

Hi everyone, I've been having difficulties with this problem for a while. Here is my best attempt at solving it. If there's anything wrong, I honestly can't figure it out :). I would appreciate if anyone could go over it quickly and tell me if/what I did wrong. Homework Statement A boat...

As all of you, I like to think about why and how Things happen; and as all of you I often feel frustrated by just how basic are the things we really don't know. What would help me at least a bit is a meaningful list of things, values, concepts that are relative (in physics), and another...

I have a question on the tension between special relativity and quantum mechanics, so please correct the category if this question is in the wrong location. I was looking at the write-up of an experiment: “Causality, relativity and quantum correlation experiments with moving reference frames”...

Hello folks! I have just come from a night at the pub with fellow students of life where over many a pint several mysteries of the universe were discussed. One of my friends asked me a question concerning special relativity that initially took me by surprise and which has me wondering about the...

Given that distance between two points can vary depending on your frame of reference wouldn't that mean that the distance between two points on a wave would vary in different frames and therefore the frequency of light would be relative. So as you speed up would this mean there would be a shift...

If a spaceship travels a distance of one light year as measured from Earth in one year's time as measured from the spaceship what is the relative velocity for earth-ship. Also how far did the pilot travel according to the pilot and how long was the trip according to an earth-clock? I found...

Sorry if this turns out to be a colossally stupid question. I'm a newbie. But since light has a constant speed in all inertial frames wouldn't that mean where it would end up would have to be relative? A famous example of relativity for things in inertial frames of reference other than...

Hi guys, I was thinking about the relativistic effects a little bit, and I have a question regarding relative simultaneity. Time dilation and length contraction grow as a function of the speed of the observer, and become noticeable and large on speeds close to the speed of light. By this...

One problem in understanding Special Relativity is that it is intuitively hard to agree with relative simultaneity. My major problem is that I cannot quite answer the question: Is relative simultaneity a real effect or only a mathematical artifact of Lorentz transformation? I am not...

I've been told on many occasions that light will always be measured at the same speed regardless of measuring equipment speed as long as there is no acceleration and you are moving the same speed relative to that object you are measuring from if that is incorrect please ignore what i say...