Two spaceships pass each other traveling in opposite directions. A passenger on ship A, which she knows to be 100-m long, notes ship B is moving with a speed of 0.920 c relative to A, and that the length of B is 36.0 m. (a) What are the lengths of the two ships as measured by a passenger on ship B? Spaceship A then travels to a star 95.0 light-years away at a speed of 2.20×108 m/s. A light year is the distance light travels in one year. How long does it take to get there (b) as measured on Earth and (c) as measured on the spaceship?

1. A spaceship A (at rest in inertial frame A) of proper length L, =75.0m is moving in the +x direction at a speed v= 0.650c as measured in the Earth frame. Another spaceship B (at rest in inertial frame B) is moving on a parallel path in the opposite direction (-x) with u, =-0.720c as measured in the Earth frame. The two spaceships pass each other. a. What is the velocity and speed parameter of spaceship B in inertial frame A, u,,B' ? b. In inertial frame A, how long does it take for the tip of spaceship B to move from the tip of spaceship A to the tail of spaceship A? c. In inertial frame B, how long does it take for the tip of spaceship B to move from the tip of spaceship A to the tail of spaceship A? d. In the Earth frame, how long does it take for the tip of spaceship B to move from the tip of spaceship A to the tail of spaceship A?

John, in his spaceship, observes as Sally, in her spaceship, passes him at a speed of v=0.8c. John who was born and raised on his spaceship, is 20 years old. According to Sally, how old is he? How many birthday parties should he have had and how many presents should Sally have sent him?

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?