Physics

Physics · modern-physics

Problem

b. In Bob's reference frame, how much time is there between when he sees Alice first fire the beam, and when he sees the beam first hit the ground? (Hint: remember to account for the travel time of light to Bob's eyes.) Given constants: ## Flashlight Alice the Mad Scientist, travelling in her flying car at height hh above the ground, shoots a beam of muons at the ground. Bob, observing from the ground at distance R≫hR \gg h from Alice's car, decides to check some facts about special relativity. Assume the muons travel extremely close to the speed of light in Alice's frame. <image_1> a. Alice's car flies at horizontal speed v=βcv=\beta c. Alice shoots her muon beam straight down, in her reference frame. Express your answers in terms of β,h,R\beta, h, R and fundamental constants. Context question: i. What is the horizontal velocity of the muons in Bob's reference frame? Context answer: v=βcv=\beta c Context question: ii. What is the vertical velocity of the muons in Bob's reference frame? Context answer: c1−β2c \sqrt{1-\beta^{2}} Context question: iii. How long does it take the muons to reach the ground in Bob's reference frame? Context answer: Δt=hc1−β2\Delta t=\frac{h}{c \sqrt{1-\beta^{2}}}

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