A rocket measures 100 m long in its own frame (S') and is travelling at 0.995c relative to a frame S. At the tail of the rocket, a laser sends out a pulse of light which is reflected by a mirror at the nose of the rocket. (a) At what time after emission, measured in S', does the light pulse arrive back at the tail of the rocket? (b) At what time after emission, measured in S, does the light pulse arrive back at the tail of the rocket? (c) What is the spatial distance, measured in S, between the emis- sion of the pulse and its arrival back at the tail of the rocket? (d) At what time after emission, measured in S, does the light pulse hit the mirror? (e) What is the spatial distance, measured in S, between the emis- sion of the pulse and its hitting the mirror? (f) Can you conclude from your answers that the light pulse travelled at a different speed, as seen in S, on its way to the mirror than on the way back? If not, explain your results

An electron moving at 0.80c relative to the Earth reference frame travels the 100m length of a building (as measured in the Earth reference frame). What is the length of the building according to an observer moving along with the electron?

Earth and a star are 20 light years (ly) apart, measured in a frame at rest with respect to Earth and star. Twin A boards a spaceship, travels at 0.80c to the star, and then returns immediately to Earth at 0.80c. Determine the round-trip travel times in Earth and ship refer- ence frames.

2.2. A rod of mass m= 1 kg flies with constant velocity past a mark which is stationary in the K frame. In the K frame, it takes the rod At= 20 ns to fly pass the mark, In the K' frame fixed to the rod, the mark moves past the rod in At' = 25 ns. (a) What is the velocity of the rod in the K frame? (b) What is the proper length of the rod? (c) What is the kinetic energy of the rod in the K frame in units of its total energy? (d) What is momentum of the rod in the K frame?

In the Marvel comics universe, Quicksilver is awfully fast. Let's say he can run at a velocity of 0.56c. He measures a trip as having a distance of 4.60e+05 m. How much time does Quicksilver measure this trip as taking? 2.73e-3 S Does Quicksilver measure the proper or dilated time? 2 proper time v Quicksilver's sister, Wanda Maximoff, is standing stationary near where he is running. How much time does Wanda measure this trip as taking? 3 3.29e-3 S What distance does Wanda measure for Quicksilver's trip? 4 Xm

A person on Earth observes two rocket ships moving directly toward each other and colliding as shown in the figure below. At time t = 0 in the Earth frame, the Earth observer determines that rocket A, travelling to the right at vA = 0.80c, is at point a, and rocket B is at point b, travelling to the left at vB = 0.60c. According to the Earth observer they are separated by a distance l = 4.2 x 108 m as shown in the other figure. How much time will elapse in frame A from the time rocket A passes point auntil collision?

The inertial reference frames, S and S', both share the same origin at t =t'=0. The S' frame is moving at a speed 0.700c in the positive direction, as seen by frame S. An event happens at (t',x', y', z') (300s, 2.50x10"m, 1.50x10"m, 2.90x10"m), as observed in the S' frame. What are the spacetime coordinates in the S frame?