11.Question 11Alice is observing the arrivals and departures at a spaceport. She observes one flight land at pad D7, and then notes another flight take off from pad G23 seventeen seconds later. Alice knows that the distance between pad D7 and pad G23 is 1240 meters in her frame of reference. Meanwhile, Bob flies by the spaceport at a high speed V and observes the same landing and takeoff, though he records a different time and distance between the two events, based on his frame of reference. If both Alice and Bob plug in their values for the elapsed time and distance between the landing and takeoff into the formulas below (where c is the speed of light, t is the elapsed time, and x is the distance), which one will give the same answer for both?1 pointc2t2 - x2ct - x2ct + x2c2t2 + x2

2.Question 2Consider a situation that is similar to that in one of the video lectures, i.e., Alice observing Bob traveling from Earth to a star at a certain distance from Earth. Assume that the Lorentz factor for the relative velocity between Alice’s frame of reference (the Earth-star frame of reference) and Bob’s frame of reference (the spaceship frame of reference) has a value of 3. Alice, in her frame of reference, measures the distance to the star as 18 light years. What is the distance from Earth to the star in Bob’s frame of reference?1 point54 light years18 light years0 light years6 light years

10.Question 10In the twin paradox example done in lecture, how does Alice explain the fact that when she returns, Bob has aged more than she has, even though on both legs of her trip when she was traveling at 0.6c she observed his clocks to run more slowly than hers?1 pointDue to the finite speed of light, there is a delay in when Alice sees the reading on one of Bob's clocks, which means that Alice's observation of Bob's clocks running slow is incorrect.When she turned around at the star, she changed her frame of reference, which led to his clocks jumping ahead of hers (from her perspective).Though it seemed to Alice as if Bob's clocks were running slower than hers, they were actually running faster throughout the whole trip.

4.Question 4The spaceships of Bob and Alice sit side-by-side at a spaceport. They measure them and both agree that each spaceship is 26 meters long. Alice takes off and Bob observes Alice's spaceship go by at a constant velocity such that the Lorentz factor is 2. Bob measures the length of his ship as Alice flies by. What value does he get?1 point52 meters13 meters26 meters

9.Question 9Consider two identical light clocks, designed as explained in lecture. Bob has one, and Alice takes the other on her spaceship and flies by Bob at speed V. Bob observes Alice’s clock. What is the relationship between a certain amount of elapsed time on Bob’s clock and the corresponding elapsed time on Alice’s clock, as observed by Bob (where γ represents the Lorentz factor)? 1 pointThe elapsed time on Alice’s clock = γ times the elapsed time on Bob’s clock.The elapsed time on Alice’s clock = (1/γ) times the elapsed time on Bob’s clock.The elapsed time on Alice’s clock = the elapsed time on Bob’s clock.

Bob is moving to the right (positive x direction) in his spaceship at a velocity v, and Alice is observing him. Each has their own lattice of clocks and measuring systems, which can be represented in two spacetime diagrams, one for Bob’s frame of reference and one for Alice’s. True or false: Bob’s world line is the line of same location given by xB = 0, whether it’s drawn on Alice’s spacetime diagram or Bob’s spacetime diagram.