Bộ tài liệu bài tập tham khảo môn vật lý bậc đại học bằng tiếng anh Chapter 39 | a X p 6-63 x10 x 10- kg. m s. p X x 10-10 m b K _ x 10 s 2 3 8 x 10 -18 2m 2 x 10kg J eV. X p j2mE x 10-J x 10-1 m. 72 x 10-27 kg x 106 eV x 10-19 J eV x h 39. 3 a Xe ------ mev __66 x XS 10-10 x 10-31 kg x 106 ms m. b V mX V9-11x 10- kg x 10-10 m 10m. p mp e x 10-27 kg a E C x 1 -V s . x 108 m s v. X x 10-9 m p1 _ vp b K ---- 2m 2m x 10-34 J-s x 10-9 m 2 2 x 10-31 kg x 10-18 J 37 eV. Note that the kinetic energy found this way is much smaller than the rest energy so the nonrelativistic approximation is appropriate. v p2 X 2 10-34 10 m _ in-22 T C K ----- ------ ---------------------- -------------- x 10 J 2m 2m 2 x 10kg meV. Again the nonrelativistic approximation is appropriate. __ . T nh a In the Bohr model mv rn . The de Broglie wavelength is 2n X -2 for n 1 r1 a x 10-11 m X1 2n x 10-11 m x 10 m. p mv n This equals the orbit circumference. b n 4 r4 4 2a0 16a0 X4 a0 4X X4 x 10-9 m. The de Broglie wavelength is a quarter of the circumference of the orbit 2nr4. p2 a For a nonrelativistic particle K so 2m X p 12Km b x 10-34 J. s 2 800eV x 10-19 J eV x 10-31 Kg x 10-11 m. h 1 - P h mv 6 63 x S x IO-5 kg 340 ms m. We should not expect the bullet to exhibit wavelike properties. Combining Equations and gives p mc y2 -1. a 1 h mc -Jy2 -1 x 10 12 m. The incorrect nonrelativistic calculation gives x 10 12 m. b h mc y2 -1 x 10 13 m. a photon hc x hc x 10-34 J s x 108 m s 1 so E eV x 10-19 J eV nm electron E p2 2m so p JlmE J2 x 10-31 kg eV x 10 J eV x 10-24 kg ms 1 h p nm b photon E hc 1 x 10-19 J eV electron 1 h p so p h 1 x 10-27 kg ms E p2 2m 10-24 J x 10-5 eV c You should use a probe of wavelength approximately 250
