C\u00e2u 9:<\/b>\u00a0Trong ph\u00f3ng x\u1ea1 c\u1ee7a h\u1ea1t nh\u00e2n\u00a0_{88<\/sub>^{226<\/sup>Ra, t\u1eeb h\u1ea1t nh\u00e2n c\u00f3 m\u1ed9t h\u1ea1t \u03b1 khi bay ra v\u1edbi \u0111\u1ed9ng n\u0103ng l\u00e0 4,78 MeV. N\u0103ng l\u01b0\u1ee3ng t\u1ecfa ra trong ph\u00f3ng x\u1ea1 n\u00e0y x\u1ea5p x\u1ec9 b\u1eb1ng<\/p>\n}}

A. 85,2 MeV \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 4,97 MeV<\/p>\n

C. 4,86 MeV \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 4,69 MeV<\/p>\n

C\u00e2u 10:<\/b>\u00a0P\u00f4l\u00f4ni\u00a0_{84<\/sub>^{210<\/sup>Po l\u00e0 ch\u1ea5t ph\u00f3ng xa tia \u03b1. Chu k\u00ec b\u00e1n r\u00e3 c\u1ee7a Po l\u00e0 138 ng\u00e0y \u0111\u00eam. H\u1eb1ng s\u1ed1 phsong x\u1ea1 c\u1ee7a p\u00f4l\u00f4ni l\u00e0<\/p>\n}}

A. 7,2.10^{-3<\/sup>\u00a0s-1<\/sup>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 5,8.10-8<\/sup>\u00a0s-1<\/sup><\/p>\n}

C. 5,02.10^{-3<\/sup>\u00a0s-1<\/sup>\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 4,02.10-8<\/sup>\u00a0s-1<\/sup><\/p>\n}

C\u00e2u 11:<\/b>\u00a0C\u00f3 hai ch\u1ea5t ph\u00f3ng x\u1ea1 A v\u00e0 B v\u1edbi h\u1eb1ng s\u1ed1 ph\u00f3ng x\u1ea1 l\u00e0 \u03bb_{1<\/sub>, \u03bb2<\/sub>\u00a0v\u1edbi \u03bb2<\/sub>=2\u03bb1<\/sub>. L\u00fac \u0111\u1ea7u ch\u00fang c\u00f3 kh\u1ed1i l\u01b0\u1ee3ng t\u01b0\u01a1ng \u1ee9ng l\u00e0 mo<\/sub>\u00a0v\u00e0 2mo<\/sub>. Kh\u1ed1i l\u1ef1ng c\u1ee7a ch\u00fang b\u1eb1ng nhau sau m\u1ed9t kho\u1ea3ng th\u1eddi gian l\u00e0<\/p>\n}

<\/p>\n

C\u00e2u 12:<\/b>\u00a0Th\u1eddi gian \u03c4 \u0111\u1ec3 s\u1ed1 h\u1ea1t nh\u00e2n ph\u00f3ng x\u1ea1 gi\u1ea3m \u0111i e = 2,7 l\u1ea7n l\u00e0 \u03c4=1\/\u03bb, trong \u0111\u00f3 \u03bb l\u00e0 h\u1eb1ng s\u1ed1 ph\u00f3ng x\u1ea1. So v\u1edbi s\u1ed1 h\u1ea1t nh\u00e2n ban \u0111\u1ea7u, sau kho\u1ea3ng th\u1eddi gian t = 2\u03c4 s\u1ed1 h\u1ea1t nh\u00e2n nguy\u00ean t\u1eed c\u1ee7a ch\u1ea5t ph\u00f3ng x\u1ea1 c\u00f2n l\u1ea1i chi\u1ebfm<\/p>\n

A. 37% \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 18,5%<\/p>\n

C. 81,5% \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 13,7%<\/p>\n

C\u00e2u 13:<\/b>\u00a0X\u00e9t s\u1ef1 ph\u00f3ng x\u1ea1 \u03b1 : A \u2192 B + \u03b1<\/p>\n

Bi\u1ebft h\u1ea1t nh\u00e2n m\u1eb9 A l\u00fac \u0111\u1ea7u \u0111\u1ee9ng y\u00ean. So s\u00e1nh \u0111\u1ed9ng n\u0103ng c\u1ee7a c\u00e1c h\u1ea1t sau ph\u00f3ng x\u1ea1 ta th\u1ea5y:<\/p>\n

<\/p>\n

C\u00e2u 14:<\/b>\u00a0\u0110\u1ec3 \u0111o chu k\u00ec b\u00e1n r\u00e3 c\u1ee7a ch\u1ea5t ph\u00f3ng x\u1ea1, ng\u01b0\u1eddi ta d\u00f9ng m\u00e1y \u0111\u1ebfm xung. B\u1eaft \u0111\u1ea7u \u0111\u1ebfm t\u1eeb t_{o<\/sub>=0 \u0111\u1ebfn t1<\/sub>=1h, m\u00e1y \u0111\u1ebfm \u0111\u01b0\u1ee3c X1<\/sub>\u00a0xung, \u0111\u1ebfn s=2h m\u00e1y \u0111\u1ebfm \u0111\u01b0\u1ee3c X2<\/sub>=1,25X1<\/sub>. Chu k\u00ec c\u1ee7a ch\u1ea5t ph\u00f3ng x\u1ea1 \u0111\u00f3 l\u00e0<\/p>\n}

A. 60 ph\u00fat \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 45 ph\u00fat<\/p>\n

C. 30 ph\u00fat \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 15 ph\u00fat<\/p>\n

C\u00e2u 15:<\/b>\u00a0C\u00f3 hai kh\u1ed1i ch\u1ea5t ph\u00f3ng x\u1ea1 A v\u00e0 B v\u1edbi chu k\u00ec ph\u00f3ng x\u1ea1 l\u1ea7n l\u01b0\u1ee3t l\u00e0 T_{1<\/sub>\u00a0v\u00e0 T2<\/sub>. Bi\u1ebft T2<\/sub>\u00a0< T1<\/sub>. S\u1ed1 h\u1ea1t nh\u00e2n ban \u0111\u1ea7u trong hai kh\u1ed1i ch\u1ea5t \u1ea5y l\u1ea7n l\u01b0\u1ee3t l\u00e0 No<\/sub>\u00a0v\u00e0 4No<\/sub>. Th\u1eddi gian \u0111\u1ec3 s\u1ed1 l\u01b0\u1ee3ng hai h\u1ea1t nh\u00e2n A v\u00e0 B c\u1ee7a hai kh\u1ed1i ch\u1ea5t c\u00f2n l\u1ea1i b\u1eb1ng nhau l\u00e0<\/p>\n}

<\/p>\n

C\u00e2u 16:<\/b>\u00a0Ch\u1ea5t ph\u00f3ng x\u1ea1 p\u00f4l\u00f4ni\u00a0_{84<\/sub>^{210<\/sup>Po ph\u00e1t ra ph\u00f3ng x\u1ea1 \u03b1 v\u00e0 bi\u1ebfn \u0111\u1ed5i th\u00e0nh ch\u00ec\u00a082<\/sub>206<\/sup>Pb. Cho bi\u1ebft mPo<\/sub>\u00a0= 209,9828 u ; mPb<\/sub>\u00a0= 205,9744 u ; m\u03b1<\/sub>=4,0026 u v\u00e0 u = 931,5 MeV\/c2<\/sup>. N\u0103ng l\u01b0\u1ee3ng t\u1ec9a ra khi 1 mg p\u00f4l\u00f4ni ph\u00e2n r\u00e3 h\u1ebft l\u00e0<\/p>\n}}

A. 2,48.10^{6<\/sup>\u00a0J \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 2,48.105<\/sup>\u00a0J<\/p>\n}

C. 1,24.10^{7<\/sup>\u00a0J \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 1,24.106<\/sup>\u00a0J<\/p>\n}

H\u01b0\u1edbng d\u1eabn gi\u1ea3i v\u00e0 \u0111\u00e1p \u00e1n<\/b><\/p>\n\n\n\n\n

C\u00e2u<\/td>\n	9<\/td>\n	10<\/td>\n	11<\/td>\n	12<\/td>\n	13<\/td>\n	14<\/td>\n	15<\/td>\n	16<\/td>\n<\/tr>\n
\u0110\u00e1p \u00e1n<\/td>\n	C<\/td>\n	B<\/td>\n	A<\/td>\n	D<\/td>\n	B<\/td>\n	C<\/td>\n	A<\/td>\n	C<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n C\u00e2u 9:<\/b>\u00a0C<\/p>\n <\/p>\n C\u00e2u 11:<\/b>\u00a0A<\/p>\n <\/p>\n C\u00e2u 12:<\/b>\u00a0D<\/p>\n <\/p>\n C\u00e2u 13:<\/b>\u00a0B<\/p>\n <\/p>\n C\u00e2u 14:<\/b>\u00a0C<\/p>\n Trong 1 h ti\u1ebfp theo m\u00e1y \u0111\u1ebfm \u0111\u01b0\u1ee3c s\u1ed1 h\u1ea1t nh\u1ecf \u0111i 4 l\u1ea7n. \u0110i\u1ec1u \u0111\u00f3 ch\u1ee9ng t\u1ecf \u1edf th\u1eddi \u0111i\u1ec3m t = 1 h, \u0111\u1ed9 ph\u00f3ng x\u1ea1 \u0111\u00e3 gi\u1ea3m \u0111i 4 l\u1ea7n, t\u01b0\u01a1ng \u1ee9ng v\u1edbi th\u1eddi gian l\u00e0 2 chu k\u00ec<\/p>\n <\/p>\n C\u00e2u 15:<\/b>\u00a0A<\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":" C\u00e2u 9:\u00a0Trong ph\u00f3ng x\u1ea1 c\u1ee7a h\u1ea1t nh\u00e2n\u00a088226Ra, t\u1eeb h\u1ea1t nh\u00e2n c\u00f3 m\u1ed9t h\u1ea1t \u03b1 khi bay ra v\u1edbi \u0111\u1ed9ng n\u0103ng l\u00e0 4,78 MeV. N\u0103ng l\u01b0\u1ee3ng t\u1ecfa ra trong ph\u00f3ng x\u1ea1 n\u00e0y x\u1ea5p x\u1ec9 b\u1eb1ng A. 85,2 MeV \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 B. 4,97 MeV C. 4,86 MeV \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 D. 4,69 MeV C\u00e2u 10:\u00a0P\u00f4l\u00f4ni\u00a084210Po l\u00e0 ch\u1ea5t ph\u00f3ng xa tia […]<\/p>\n","protected":false},"author":3,"featured_media":25746,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"tdm_status":"","tdm_grid_status":""},"categories":[158],"tags":[1443,1442],"yoast_head":"\n