Question

3. a) As shown in Figure 3a, a hibernating astronaut in a ship at rest lies on a recliner making an angle = 35° with the horizontal. The height of the recliner is y = 1.15 meters. In Figure 3b, the ship is moving at velocity v = 0.75c with respect to a stationary observer. Calculate the value of the Lorentz factor y. What is the observed angle e' of the length-contracted recliner? Figure 3b. Relativity: 1 - 22 ť=yto Figure 3a. b) The ship travels to a nearby star, Alpha Centauri (a Cen), 4.37 light years from Earth. The astronaut has a twin who remains on Earth during the trip. Each twin is 35 years old at departure. At u= 0.75c, what are the ages of each twin when the ship completes a round-trip voyage? Assume the ship travels at constant velocity each way, and that the traveling astronaut explores planets at a Cen for one year before returning to Earth. c) A UV photon with a wavelength 2 = 200 nm strikes a copper surface having a work function Wo = 4.65 eV. What is the maximum kinetic energy of the ejected electron in eV? What is the cutoff wavelength lo corresponding to a photon with the minimum energy required to eject an electron at all? L'=L Quantum Physics: Ey = hf = h = 6.63 x 10-34 Jºs 1 eV = 1.6 x 10-19 J Ey = W. + Ke

Answer 1

② ② V 0.750 V= 0.75c 1 - 0.45)? (M = 1.51 - d= 4.37 light years t - (d+d) + 1(you) - 4.37* (3x103) x 1 year at 1 year) 0.75 x(3363 : 5.82667 + 1 [t= 6, 82667 years the observer on the stationary frame will be of age → 35+ 6.82667 = 41.83 year :

moving astronant will be of. 35+ 6.82667 - 3 6-82667 1.51 = 39.52 years The moring them Astronaut will be the stationary one. younger a= 200 um , p=W = 4.66 eV KE = hd - 6 =hcº 3 1240 - 4.65 200 (KEM 1.55 evl of the elections Cut off were length do 1240 - 20 c m 266.66 mm