Đang chuẩn bị nút TẢI XUỐNG, xin hãy chờ
Tải xuống
Bộ tài liệu bài tập tham khảo môn vật lý bậc đại học bằng tiếng anh Chapter 40 | Âni . n2h2 h2 6.63 x10-34J s 2 40.1 a E --------- E1 --------- n 8mL2 1 8mL2 8 0.20 kg 1.5 m 2 E1 1.22 x 10 6 7 J. 1 b E mv 2 2 EE 2 1 2x 10 67 J V m y 0.20 kg 1.1 x 10 33m s d t v ----1.5m 1.4 x 1033 s. 1.1 x 10 33 ms h1 3h2 c E2 E1 m 4 1 m 3 1 22x 10 J 3.7x 10 J. d No. The spacing between energy levels is so small that the energy appears continuous and the balls particle-like as opposed to wave-like . 40.2 L yj8mE1 40.3 6.626 x 10-34 J s 6.4 x 10-15 m. 78 1.673 x 10-27 kg 5.0 x 106eV 1.602 x 10-19 J eV h2 3h 2 E2-E1 - 2 4-1 h- L h 8mL2 8mL2 8m E2 - E1 3 3 6.63 x 10-34 J s J----------------------------rj ----- 8 9.11 x 10-31 kg 3.0eV 1.60x 10-19 J eV L 6.1x 10 10 m 0.61 nm. 40.4 a The energy of the given photon is 77 ic m-34 t x 3.00 x 103 m s 18 - E hf h 6.63 x 10 J s ---------7---- 1.63 x 10 J. X 122 x 10-9m The energy levels of a particle in a box are given by Eq. 40.9 h2 . 2 2 T lh2 n2-m2 I 6.63 x 10-34 J s 2 22-12 AE n- m2 L 8mL2 N 8mAE 8 9.11x 10-31 kg 1.63 x 10-20J 3.33x 10-10 m. b The ground state energy for an electron in a box of the calculated dimensions is E -h-T 6-63 10 s 5.43 x 10-19 J 3.40 eV one-third of the original 8mL2 8 9.11 x10-31 kg 3.33 x10-10m 2 photon energy which does not correspond to the -13.6 eV ground state energy of the hydrogen atom. Note that the energy levels for a particle in a box are proportional to n2 whereas the energy levels for the hydrogen atom are proportional to - 2 . 40.5 E 2mv1 5.00 x 10 3 kg 0.010m s 2 2.5 x 10-7 J M h2 T h b E ------- so L . 8mL -j8mE1 E 2.5 x 10 7 J gives L 6.6 103 m The wave function for n 1 vanishes only at x 0 and x L in the range b In the range for x the sine term is a maximum only at the middle of the 40.6 a 0 x L. box x L 2. c The answers to parts a and b are consistent with the figure. 40.7 The first excited state or n 2 wave function is 2 x o 1 x 2 2.2 f 2nx So 2 x -sin l L L . . 2f 2nx a If the probability amplitude is zero then sin l--I 0 L J 2 x mn x Lm m 0 1 2 . . L 2 So probability is .
