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18.9: Mstari wa Mstari na Migongano
https://query.libretexts.org/Kiswahili/Chuo_Kikuu_Fizikia_I_-_Mitambo%2C_Sauti%2C_oscillations%2C_na_Waves_(OpenStax)/18%3A_Jibu_muhimu_kwa_Matatizo_Yaliyochaguliwa/18.09%3A_Mstari_wa_Mstari_na_Migongano
Radius wastani wa obiti ya Dunia kuzunguka Jua ni 1.496 x 10 9 m Kuchukua Jua kuwa asili, na kubainisha kuwa masi ya Jua ni takriban sawa na raia wa Jua, Dunia, na Mwezi pamoja, katikati ya masi ya Du...Radius wastani wa obiti ya Dunia kuzunguka Jua ni 1.496 x 10 9 m Kuchukua Jua kuwa asili, na kubainisha kuwa masi ya Jua ni takriban sawa na raia wa Jua, Dunia, na Mwezi pamoja, katikati ya masi ya Dunia + mfumo wa Mwezi na Jua ni $$\ kuanza {split} R_ {CM} & =\ frac {m_ {Sun} R_ {Sun} + m_ {em} R_ {em}} {m_ {Sun}}\\ & =\ Frac {(1.989\ mara 10^ {30}\; kg) (0) + (5.97\ mara 10^ {24}\; kilo + 7.36\ mara 10^ {22}\; kg) (1.97\ 496\ mara 10^ {9}\; m)} {1.989\ mara 10^ {30}\; kg}\\ & = 4.6\; km\ mwis…
18.9: 线性动量和碰撞
https://query.libretexts.org/%E7%AE%80%E4%BD%93%E4%B8%AD%E6%96%87/%E5%A4%A7%E5%AD%A6%E7%89%A9%E7%90%86%E5%AD%A6_I-%E5%8A%9B%E5%AD%A6%E3%80%81%E5%A3%B0%E9%9F%B3%E3%80%81%E6%8C%AF%E8%8D%A1%E5%92%8C%E6%B3%A2%E6%B5%AA_(OpenStax)/18%3A_18%EF%BC%9A%E9%80%89%E5%AE%9A%E9%97%AE%E9%A2%98%E7%9A%84%E7%AD%94%E6%A1%88%E5%85%B3%E9%94%AE/18.09%3A_%E7%BA%BF%E6%80%A7%E5%8A%A8%E9%87%8F%E5%92%8C%E7%A2%B0%E6%92%9E
9.12。在宏观尺度上，单位电池的大小可以忽略不计，可以认为晶体质量在整个晶体中均匀分布。因此，$$\ vec {r} _ {CM} =\ frac {1} {M}\ sum_ {j = 1} ^ {N} m_ {j}\ vec {r} _ {j} =\ frac {1} {m} =\ frac {m} {m} sum_ {j = 1} ^ {N}\ vec {r} _ {j} =\ frac...9.12。在宏观尺度上，单位电池的大小可以忽略不计，可以认为晶体质量在整个晶体中均匀分布。因此， $\ vec {r} _ {CM} =\ frac {1} {M}\ sum_ {j = 1} ^ {N} m_ {j}\ vec {r} _ {j} =\ frac {1} {m} =\ frac {m} {m} sum_ {j = 1} ^ {N}\ vec {r} _ {j} =\ frac {Nm} {M}\ frac {\ sum_ {j = 1} ^ {N}\ vec {r} _ {j}} {N}$ 其中我们求和晶体中 N 个单位单元的质量。因为 Nm = M，我们可以写 $$\ vec {r} _ {CM} =\ frac {m} {M}\ sum_ {j = 1} ^ {N}\ vec {r} _ {j} =\ frac {\ sum_ {j} ^ {N}\ vec {r} _ {n} {n}\\ frac c {1} {N}\ sum_ {j = 1} ^ {N}\ vec {r} _ {j}\ ldotp$这是晶体几何中心的定义，所以质心与几何位于同一点中心。
18.9 : Moment linéaire et collisions
https://query.libretexts.org/Francais/Physique_universitaire_I_-_M%C3%A9canique%2C_son%2C_oscillations_et_ondes_(OpenStax)/18%3A_La_cl%C3%A9_de_r%C3%A9ponse_%C3%A0_certains_probl%C3%A8mes/18.09%3A_Moment_lin%C3%A9aire_et_collisions
En prenant le Soleil comme origine et en notant que la masse du Soleil est approximativement la même que les masses du Soleil, de la Terre et de la Lune combinées, le centre de masse du système Terre+...En prenant le Soleil comme origine et en notant que la masse du Soleil est approximativement la même que les masses du Soleil, de la Terre et de la Lune combinées, le centre de masse du système Terre+Lune et du Soleil est $$ \ begin {split} R_ {CM} & = \ frac {m_ {Soleil} R_ {Soleil} + m_ {em} R_ {em}} {m_ {Soleil}} \ \ & = \ frac {(1,989 \ fois 10^ {30} \ ; kg) (0) + (5,97 \ fois 10^ {24} \ ; kg + 7,36 \ fois 10^ {22} \ ; kg) (1,496 \ times 10^ {9} \ ; m)} {1,989 \ times 10^ {30} \ ; kg} \ \ &…
18.9: Momento linear e colisões
https://query.libretexts.org/Idioma_Portugues/Fisica_Universitaria_I_-_Mecanica_Som_Oscilacoes_e_Ondas_(OpenStax)/18%3A_Chave_de_resposta_para_problemas_selecionados/18.09%3A_Momento_linear_e_colis%C3%B5es
Se o carrinho menor estivesse rolando a 1,33 m/s para a esquerda, a conservação do momentum dá $$\ begin {split} (m_ {1} + m_ {2})\ vec {v} _ {f} & = m_ {1} v_ {1}\;\ hat {i} − m_ {2} v_ {2}\;\ hat {i...Se o carrinho menor estivesse rolando a 1,33 m/s para a esquerda, a conservação do momentum dá $\ begin {split} (m_ {1} + m_ {2})\ vec {v} _ {f} & = m_ {1} v_ {1}\;\ hat {i} − m_ {2} v_ {2}\;\ hat {i}\\ vec {v} _ {f} & =\ left (\ dfrac {m_ {1} v_ {1} − m_ {2} v_ {2}} {m_ {1} + m_ {2}}\ direita)\;\ hat {i}\ & =\ Bigg [\ frac {(0,675\; kg) (0,75\; m/s) − (0,500\; kg) (1,33\; m/s)} {1,175\; kg}\ Bigg]\;\ hat {i}\\ & = − (0,135\; m/s)\;\ hat {i}\ end {split}$ Assim, a velocidade final é de 0,135…
18.9: الزخم الخطي والتصادمات
https://query.libretexts.org/%D8%A7%D9%84%D9%84%D8%BA%D8%A9_%D8%A7%D9%84%D8%B9%D8%B1%D8%A8%D9%8A%D8%A9/-_____(OpenStax)/18%3A_%D9%85%D9%81%D8%AA%D8%A7%D8%AD_%D8%A7%D9%84%D8%A5%D8%AC%D8%A7%D8%A8%D8%A9_%D8%B9%D9%84%D9%89_%D8%A7%D9%84%D9%85%D8%B4%D8%A7%D9%83%D9%84_%D8%A7%D9%84%D9%85%D8%AD%D8%AF%D8%AF%D8%A9/18.09%3A_%D8%A7%D9%84%D8%B2%D8%AE%D9%85_%D8%A7%D9%84%D8%AE%D8%B7%D9%8A_%D9%88%D8%A7%D9%84%D8%AA%D8%B5%D8%A7%D8%AF%D9%85%D8%A7%D8%AA
وهكذا، $$\ vec {r} _ {سم} =\ frac {1} {M}\ sum_ {j = 1} ^ {N} m_ {j}\ vec {r} _ {j} =\ frac {1} {م}\ سوم_ {j = 1} ^ {N} م\ فيك {r} {j} = {j}\ sum_ {n} م\ فيك {j} = {j} =\ frac {1} {j}\ sum_ j = 1} ^ {...وهكذا، $$\ vec {r} _ {سم} =\ frac {1} {M}\ sum_ {j = 1} ^ {N} m_ {j}\ vec {r} _ {j} =\ frac {1} {م}\ سوم_ {j = 1} ^ {N} م\ فيك {r} {j} = {j}\ sum_ {n} م\ فيك {j} = {j} =\ frac {1} {j}\ sum_ j = 1} ^ {N}\ vec {r} _ {j} =\ frac {Nm} {M}\ frac {\\ sum_ {j = 1} ^ {N}\ vec {r} _ {j} {N} {N}} {N} $حيث نجمع عدد N من خلايا الوحدة في البلورة وm هي كتلة خلية الوحدة.