Spaceship Definition and 222 Threads

This is another version of bell’s spaceship paradox. Consider two spaceships A & A’ separated by a distance L, and are tied by a non elastic thread. They are on earth. This time the two spaceships are not moving instead I'm moving. I’m in a distant planet and i starts to accelerate and reach at...

In relativity of simultaneity, it is said like simultaneous events for one observer is not simultaneous for another. Does that mean events been seen from one observers point of view may not be true? For example consider the bell’s spaceship paradox From my point of view the "silk thread"...

Homework Statement A spaceship of mass ##m_0## moves in the absence of external forces with a constant velocity ##v_0##. To change the motion direction, a jet engine is switched on. It starts ejecting a gas jet with velocity u which is constant relative to the spaceship and directed at right...

Homework Statement Spaceship is ##\scriptsize100m## long in its proper coordinate system and is moving relative to Earth. Astronaut sends a light signal from the rear part of the spaceship towards the front part. It seems to an observer on Earth, that a light signal needed ##\scriptsize 0.57\mu...

This is probably a silly question, but I want to make sure I get it right for a story I'm writing. I want to roll an elongated spaceship "around" it's horizontal axis (as opposed to flipping it end over end). Is it equivalent to say "along" the horizontal axis? In this case, I'm assuming...

Can someone please clarify for me whether length contraction in special relativity is considered a physical effect (a contraction of a cohesive material) or a kinematic effect (applied to the space the material occupies)? I've been thinking about Bell's Spaceship Paradox this week and realized...

Homework Statement i put my answers to the questions in bold A spaceship and its occupants have a total mass of 1.8×105kg . The occupants would like to travel to a star that is 30 light-years away at a speed of 0.70c. To accelerate, the engine of the spaceship changes mass directly to energy...

Homework Statement A spaceship is powered by a matter-antimatter reactor. Suppose you have a 23000-metric-ton spaceship and wish to accelerate it to 0.03 c. What is the total mass of matter and anti matter required, assuming a 100 % efficient engine. Homework Equations Really not sure about...

A spaceship moves near the speed of light. Its time becomes slow for an observer on earth. 1. Does 'time' slow only in and around ( i.e. the space inside and outside) the spaceship? If yes, to what extent ( i.e. how much meters or centimeters) above the physical boundary of spaceship. 2...

Is the energy of a rotating cylindrical spacecraft conserved when a point-like astronaut climbs up a spoke connecting the walls with the center of the cylinder? If so, when I calculate the fractional change in apparent gravity at the walls when the astronaut reaches the middle I get different...

Homework Statement The spacecraft P is in the elliptical orbit shown. At the instant represented, its speed is v = 13164 ft/sec. Determine the corresponding values of and . Use g = 32.23 ft/sec2 as the acceleration of gravity on the surface of the Earth and R = 3959 mi as the radius of the...

So what would happen if there was a spaceship moving at 99% the speed of light straight up. The spaceship has a light clock, so a photon of light moving bouncing between 2 mirrors in such a way that the light moves ALMOST in sync with the spaceship moving up. In theory wouldn't the light photon...

Homework Statement A spaceship travel from Earth \alpha-Centauri (4.3 light years away) at a constant velocity. If the time elapsed onboard during the journey is 4.e years, what is the speed of the spaceship? The spaceship is powered by a drive which works by ejecting protons behind the ship...

Hi all, I think this question goes best in this section, because I think the answer is something a nuclear or particle scientist could answer. In space, what would happen to a ship that did not have proper shielding from cosmic rays? (NOT the astronauts themselves; there is plenty of...

I have been reading a lot of relativity-related material and clearing up a few gaps in my general knowledge. I read something that struck me as off. Perhaps I am missing something. Usenet Physics FAQ -> The Relativistic Rocket http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html...

Homework Statement The position function of a spaceship is r(t)= < 3+T, 2+ln(T), 7 -(4/T2+1)> , and the coordinates of a space station are (6, 4, 9). The captain wants to coast into the space station. When should the engines be turned off? Homework Equations I took the derivative of the...

I've been thinking about the speed of light, and if it is possible to exceed it. So, I came up with my spaceship on a lever theory. Essentially, you have a long lever with a fulcrum near one end. At the other end, you attach a spaceship. Next, you apply pressure at the short end of the...

Homework Statement Spaceship #1 moves with a velocity of .2c in the positive x direction of reference frame S. Spaceship #2, moving in the same direction with a speed of .6c is 3 x 10^9 m behind. At what times in reference frames S, and in the reference frame of ship #1, will 2 catch up with...

If i was standing on the Earth at rest and a spaceship traveling at 0.99c passed by and flashed a light for a very small amount of time would this time appear longer for me or the pilot of the spaceship?

Homework Statement ESTIMATE the Lorentz factor of a spaceship which travels to a nearby star 10pc from the solar system in 50 years spaceship time. Homework Equations Lorentz factor: γ = 1/√(1 - v^2/c^2 ) Time dilation: Δt' = γΔt The Attempt at a Solution Using the distance...

Homework Statement A rocket on its way to the moon passes through point P (along the line connecting the Earth and the moon) where the gravitational pull by the moon is exactly equal to the gravitational pull by the earth. Neglect the motions of the moon and the Earth and find the...

Homework Statement At 11h 0m 0.0000s AM a boiler explodes in the basement of the Denver Science Museum. At 11h 0m 0.0003s, a similar boiler explodes in the basement of a ski lodge in Aspen at a distance of 150 km from the first explosion. Show that in the reference frame of a spaceship moving...

Homework Statement Spinning Space Ship One way to provide artificial gravity (i.e., a feeling of weight) on long space voyages is to separate a spacecraft into two parts at the ends of a long cable, and set them rotating around each other. A craft has been separated into two parts with a...

Spaceship A and spaceship b are traveling at 99.99... % the speed of light. Spaceship A is behind spaceship B. Spaceship A wants to destroy spaceship B and fires a missile. Will spaceship A succeed for any velocity the rocket is launched at and at a variable distance?

Hi, my knowledge on physics is very rudimentary but I have been googling. So, I wanted to ask is there a way for a spaceship to be absolutely still in space? I thought about having an eye-shaped spacecraft and thrusters on all sides (360 degree), but if they're all on at once the force would...

Hello, Suppose, A and B spaceships are moving with constant acceleration. There is a string tied to spaceships center to center. A is on left of B and B is on right of A. C is outside observer. As speed increase, A sees that B going further ahead, and B sees A going further behind. So, from...

Homework Statement Two spaceships having rest length 100 m pass each other traveling opposite directions with a relative speed of 0.901 c As the front of the spaceships just cross, each pilot sets off a small flare at the back of her own ship, synchronized to the same instant (t=0 in her own...

Homework Statement Suppose our sun is about to explode and we escape in a spaceship toward the star Tau Ceti. When we reach the midpoint of our journey, which takes place at v=.83 C we see our sun explode and, unfortunately, we see Tau Ceti explode as well (we observe the light arriving from...

I'm writing a science fiction story and have a basic understanding of theoretical propulsion systems (ramjets, ion drives, solar sails, etc.). But I'm also trying to make my story plausible. So, that means no faster-than-light travel, infinite energy sources, artificial gravity generators, etc...

Background This started out as a question, but answered itself in the process of being written up. I thought I'd post it anyway, in case it might help clarify something for someone else. It is an alternative derivation of the solution to a (similar) question asked in Six Not-So-Easy Pieces...

On several homework questions I have encountered the following type of scenario: Two clocks are perfectly synchronized. One is placed in a spaceship, and the other is left on the ground. The spaceship flies to some distant location at some high speed, and then returns to earth. When the...

Homework Statement The distance from Planet X to a nearby star is 12 Light-Years (a light year is the distance light travels in 1 year as measured in the rest frame of Planet X). (A) How fast must a spaceship travel from Planet X to the star in order to reach the star in 7 years...

Homework Statement A relativistic spaceship is moving "horizontally" past Earth at 99% speed of light (c), and the water in the ship's swimming pool rises at 5 m/s. What is the tilt of the water surface with respect to the horizontal, AS OBSERVED FROM EARTH?Homework Equations The Attempt at a...

Homework Statement The Position Function of a spaceship is r(t) = (5t+9)i+(2t2-1)j+t2k and the coordinates of a space station are P(54,89,45). The captain wants the spaceship to reach the space station in constant velocity. When should the engines be turned off? Homework Equations r'(t)...

Say I became a particle and I'm moving at 0.9c towards a spaceship. My course is parallel to the ship, and I'm seeing it bow first. So the entire ship is initially in front of me, seems quite short and is highly blue-shifted, right? So any crew would seem to be quite blue and is moving around...

Homework Statement A spaceship launched from a space station was moving with a speed 0.6c , with respect to the space station , in a direction perpendicular to its motion , when , a band of asteroids is observed a head of the ship. A proton gun is shut by the spaceship with a speed of 0.99c...

Hi, I am trying to understand this Bell's Spaceship Paradox , which is basically asking when there is a thread connected between two spaceship (A,B) and an observer C observes a "constant" acceleration, then whether this thread will break or not by Lorentz Contraction. I think the problem...

If u stand on top of a spaceship, u will not be thrust backward? U only do on top of an airplane because of air resistance? So if u jump up out of a horizontally moving spaceship, after you jump out you are moving with the same horizontal speed as you were inside the spaceship? U just have to...

Homework Statement The nearest star to Earth is Proxima Centauri, 4.3 light-years away. At what constant velocity must a spacecraft travel from Earth if it is to reach the star in 3.7 years, as measured by travelers on the spacecraft ? How long does the trip take according to Earth...

For example if the pulsar is rotating with a fourth of the speed of light? Or more generally, what effect does the rotation of an object have when it comes to landing on it? Thanks

I am writing a 2d computer game and need some help. I have a spaceship that is moving(or stationary) and I want to move it to a destination coordinate. Here are the main variables: Const PI = 3.14159 'Mmmm.. Pi Const ACCEL = 0.1 'Rate of increase of speed Const...

I have been pondering but cannot quite resolve the following question: Imagine two spaceships, separated by 4 light-seconds initially. Spaceship A is traveling at 0.8c and Spaceship B (the one with the lead) is traveling at 0.4c. Clearly an external observer will see this "chase" last for...

Hi, Please consider: At time zero a spaceship takes off from Earth and keeps traveling under constant acceleration. From Earth's perspective, the spaceship's speed keeps increasing but never reaches c. Also from Earth's perspective, the clock on the spaceship keeps slowing down and...

Hi! First of all, I just want to say that I don't know much about general relativity. But my question concerns an example often found in textbooks about special relativity. On to my question. I have heard several times that one can travel forward in time (earth-time) by leaving earth...

How plausible are these concepts? Thomas Ciesla's Centauri project utilizes a terraformed asteroid with antimatter propulsion that can travel at .30 c Alan Holt's interstellar transport system uses two field generators and 16 field amplifiers to create a space-time bubble around a vessel...

Does that mean the spaceship has become bigger or denser up to the subatomic level? Or is it just more atoms have stuck to the spaceship? What happens when it slows down? The added mass just 'evaporates'?

Hello. Some years ago I came across an animated illustration of relativity, housed in what seems to be a classic use of a bouncing light within a spaceship. (Similar to that found in http://galileoandeinstein.physics.virginia.edu/lectures/srelwhat.html.) My education in physics is limited to...

Hi, I'm reading the excellent explanation of this paradox at http://www2.corepower.com:8080/~relfaq/spaceship_puzzle.html but have become confused by the wording in this paragraph: It could just be me missing something but this paragraph seems contradictory. When he says draw a line...

If you were in a spaceship that was going JUST under light speed & you ran forward... If you were in a spaceship that was traveling JUST under light speed & you ran forward towards the front of the Spaceship, what would happen? I'm talking literally JUST under c, like 0.999999999999999999999...

Homework Statement Spaceship with proper length 100m is moving at 0.2c in +x direction. In the back and front of the spaceship is a light source. a. When the light in the back is turned on, how long will it take for the light to reach the front of the spaceship? b. How about the light in...