Question Number 99537 by Dwaipayan Shikari last updated on 21/Jun/20
$$\mathrm{Suppose}\:\mathrm{your}\:\mathrm{weight}\:\mathrm{is}\:\mathrm{50kg}\:\mathrm{and}\:\mathrm{you}\:\mathrm{are}\:\mathrm{taking}\:\mathrm{rest}. \\ $$$$\mathrm{what}\:\mathrm{is}\:\mathrm{the}\:\mathrm{de}-{brogli}\:\mathrm{wavelength}\:\mathrm{associated}\:\mathrm{by}\:\mathrm{you}. \\ $$$$\left(\mathrm{Respect}\:\mathrm{to}\:\mathrm{the}\:\mathrm{universal}\:\mathrm{system}\right)\left[\mathrm{suppose}\:\mathrm{another}\:\mathrm{one}\:\mathrm{who}\:\mathrm{is}\:\right. \\ $$$$\left.\mathrm{calculating}\:\mathrm{your}\:\mathrm{wavelength}\:\mathrm{is}\:\mathrm{on}\:\mathrm{space}\right] \\ $$
Answered by smridha last updated on 21/Jun/20
$$\boldsymbol{{meaningless}}\:\boldsymbol{{question}}.. \\ $$$$\boldsymbol{{weight}}=\mathrm{50}\:\boldsymbol{{kg}}!!\:\boldsymbol{{that}}'\boldsymbol{{s}}\:\boldsymbol{{not}}\:\boldsymbol{{right}} \\ $$$$\boldsymbol{{it}}\:\boldsymbol{{should}}\:\boldsymbol{{be}}\:\boldsymbol{{mass}}. \\ $$$$\boldsymbol{{de}}−\boldsymbol{{broglie}}\:\boldsymbol{{formula}}\:\boldsymbol{{valid}}\:\boldsymbol{{for}} \\ $$$$\boldsymbol{{quantum}}\:\:\boldsymbol{{world}}… \\ $$$$\boldsymbol{{are}}\:\boldsymbol{{you}}\:\boldsymbol{{quantum}}\:\boldsymbol{{particle}}?? \\ $$$$\boldsymbol{{wavelength}}\:\boldsymbol{{is}}\:\boldsymbol{{very}}\:\boldsymbol{{negligible}}. \\ $$$$\boldsymbol{{and}}\:\boldsymbol{{also}}\:\boldsymbol{{you}}\:\boldsymbol{{are}}\:\boldsymbol{{in}}\:\boldsymbol{{rest}}..\boldsymbol{{so}}\:\boldsymbol{{it}}'{s} \\ $$$$\boldsymbol{{meaningless}}..{to}\:\boldsymbol{{use}}\:\boldsymbol{{de}}\:−\boldsymbol{{brogli}}{e}. \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${Earth}\:{is}\:{rotating}\:{about}\:{his}\:{axis}\:{with}\:{a}\:{speed}\:{of}\:\mathrm{30}{km}/{s}\left({approx}\right) \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${Sorry}!\:{It}\:{is}\:{mass}\:.{I}\:{used}\:{the}\:{usual}\:{speech}\:{like}\:{weight}. \\ $$
Commented by smridha last updated on 21/Jun/20
$$\boldsymbol{{earth}}\:\boldsymbol{{also}}\:\boldsymbol{{moves}}\:\boldsymbol{{round}}\:\boldsymbol{{the}}\:\boldsymbol{{sun}} \\ $$$$\boldsymbol{{at}}\:\boldsymbol{{a}}\:\boldsymbol{{speed}}\:\boldsymbol{{v}}=\sqrt{\boldsymbol{{gr}}}..\boldsymbol{{and}}\: \\ $$$$\boldsymbol{{we}}\:\boldsymbol{{also}}\:\boldsymbol{{don}}'{t}\:\boldsymbol{{know}}\:\boldsymbol{{the}}\:\boldsymbol{{velocity}} \\ $$$$\boldsymbol{{of}}\:\boldsymbol{{frame}}\:\boldsymbol{{where}}\:\boldsymbol{{we}}\:\boldsymbol{{measure}}.. \\ $$$$\boldsymbol{{and}}\:\:\boldsymbol{{the}}\:\boldsymbol{{most}}\:\boldsymbol{{important}}\:\boldsymbol{{thing}} \\ $$$$\boldsymbol{{can}}\:\boldsymbol{{we}}\:\boldsymbol{{use}}\:\boldsymbol{{de}}−\boldsymbol{{broglie}}\:\boldsymbol{{formula}} \\ $$$$\boldsymbol{{in}}\:\boldsymbol{{that}}\:\boldsymbol{{case}}..\boldsymbol{{because}}\:\boldsymbol{{we}}\:\boldsymbol{{are}}\:\boldsymbol{{not}} \\ $$$$\boldsymbol{{quantum}}\:\boldsymbol{{particle}}… \\ $$$$ \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${suppose}\:{the}\:{frame}\:{is}\:{inertial} \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${I}\:{also}\:{know}\:{it}\:{is}\:{a}\:{stupid}\:{question}.\:{But}\:{i}\:{am}\:{trying}\:{to}\:{visualise}\:{those}\:{things} \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${I}\:{am}\:{sorry}\:{as}\:{i}\:{am}\:{spending}\:{your}\:{valuable}\:{time}. \\ $$
Commented by Dwaipayan Shikari last updated on 21/Jun/20
$${I}\:{am}\:{a}\:{student}\:{so}\:{i}\:{want}\:{to}\:{learn}\:{more}. \\ $$
Commented by smridha last updated on 22/Jun/20
$$\boldsymbol{{well}}\:\boldsymbol{{I}}\:\boldsymbol{{consider}}\:\boldsymbol{{it}}\:\boldsymbol{{is}}\:\boldsymbol{{a}}\:\boldsymbol{{non}}−\boldsymbol{{R}}{e}\boldsymbol{{lativistic}} \\ $$$$\boldsymbol{{case}}… \\ $$$$\boldsymbol{{then}}\:\boldsymbol{{if}}\:\boldsymbol{{the}}\:\boldsymbol{{frame}}\left(\boldsymbol{{lets}}\:\boldsymbol{{say}}\:\boldsymbol{{s}}^{'} \right)\:\boldsymbol{{is}}\:\boldsymbol{{inertial}} \\ $$$$\boldsymbol{{to}}\:\boldsymbol{{our}}\:\boldsymbol{{lab}}−\boldsymbol{{frame}}\:\boldsymbol{{then}}\:\boldsymbol{{the}}\:\boldsymbol{{observer}} \\ $$$$\boldsymbol{{who}}\:\boldsymbol{{watching}}\:\boldsymbol{{over}}\:\boldsymbol{{you}}\:\boldsymbol{{from}}\:\boldsymbol{{s}}^{'} , \\ $$$$\boldsymbol{{see}}\:\boldsymbol{{you}}\:\boldsymbol{{are}}\:\boldsymbol{{standing}}\:\boldsymbol{{still}}\:\boldsymbol{{in}}\:\boldsymbol{{rest}}. \\ $$$$\boldsymbol{{so}}\:\boldsymbol{{relative}}\:\boldsymbol{{velocity}}\:\boldsymbol{{v}}_{\boldsymbol{{rel}}} =\mathrm{0} \\ $$$$\boldsymbol{{so}}\:\boldsymbol{{your}}\:\boldsymbol{{de}}−\boldsymbol{{broglie}}\:\boldsymbol{{wavelength}} \\ $$$$\boldsymbol{{is}}\:\boldsymbol{\lambda}\Rightarrow\infty.\boldsymbol{{I}}\:\boldsymbol{{am}}\:\boldsymbol{{not}}\:\boldsymbol{{satisfied}}\:\boldsymbol{{with}} \\ $$$$\boldsymbol{{this}}\:\boldsymbol{{ans}}…\boldsymbol{{are}}\:\boldsymbol{{you}}???\boldsymbol{{it}}'{s}\:\boldsymbol{{fail}}\:\boldsymbol{{to}} \\ $$$$\boldsymbol{{describe}}\:\boldsymbol{{the}}\:\boldsymbol{{physical}}\:\boldsymbol{{nature}}… \\ $$$$\boldsymbol{{because}}\:\infty\:\boldsymbol{{is}}\:\boldsymbol{{just}}\:\boldsymbol{{a}}\:\boldsymbol{{concept}}\:\boldsymbol{{it}}\:\boldsymbol{{cannot}} \\ $$$$\boldsymbol{{be}}\:\boldsymbol{{ans}}..\boldsymbol{{no}}\:\boldsymbol{{one}}\:\boldsymbol{{can}}\:\boldsymbol{{know}}\:\boldsymbol{{what}} \\ $$$$\boldsymbol{{it}}\:\boldsymbol{{is}}.. \\ $$
Commented by Dwaipayan Shikari last updated on 22/Jun/20
But respect to the inertial frame I was moving at a speed of 30 km/s. And at an instant of time earth revolving speed may be neglected
Commented by smridha last updated on 22/Jun/20
$$\boldsymbol{{what}}\:\boldsymbol{{is}}\:\boldsymbol{{inertial}}\:\boldsymbol{{frame}}\:\boldsymbol{{of}}\:\boldsymbol{{reference}}??? \\ $$$$\left(\boldsymbol{{i}}\right)\boldsymbol{{a}}\:\boldsymbol{{frane}}\:\boldsymbol{{which}}\:\boldsymbol{{is}}\:\boldsymbol{{moving}}\:\boldsymbol{{with}} \\ $$$$\boldsymbol{{uniform}}\:\boldsymbol{{velocity}} \\ $$$$\left(\boldsymbol{{ii}}\right)\boldsymbol{{a}}\:\boldsymbol{{frame}}\:\boldsymbol{{which}}\:\boldsymbol{{is}}\:\boldsymbol{{stanting}} \\ $$$$\boldsymbol{{at}}\:\boldsymbol{{rest}}\:\boldsymbol{{and}}\:\boldsymbol{{another}}\:\boldsymbol{{frame}}\:\boldsymbol{{is}}\: \\ $$$$\boldsymbol{{moving}}\:\boldsymbol{{with}}\:\boldsymbol{{constant}}\:\boldsymbol{{speed}}\:\boldsymbol{{respect}} \\ $$$$\boldsymbol{{to}}\:\boldsymbol{{that}}\:\boldsymbol{{frame}}..\boldsymbol{{in}}\:\boldsymbol{{that}}\:\boldsymbol{{case}}\:\mathrm{1}\boldsymbol{{st}}\:\boldsymbol{{frame}} \\ $$$$\boldsymbol{{is}}\:\boldsymbol{{also}}\:\boldsymbol{{a}}\:\boldsymbol{{inertial}}\:\boldsymbol{{frame}}. \\ $$$$\boldsymbol{{I}}\:\boldsymbol{{consider}}\:\boldsymbol{{a}}\:\boldsymbol{{frame}}\:\boldsymbol{{which}}\:\boldsymbol{{has}} \\ $$$$\boldsymbol{{uniform}}\:\boldsymbol{{velocity}}\:\boldsymbol{{as}}\:\boldsymbol{{same}}\:\boldsymbol{{as}}\:\boldsymbol{{earth}}. \\ $$$$\boldsymbol{{rotational}}\:\boldsymbol{{speed}}\:\boldsymbol{{about}}\:\boldsymbol{{its}}\:\boldsymbol{{own}}\:\boldsymbol{{axies}}\:\boldsymbol{{and}} \\ $$$$\boldsymbol{{revolvig}}\:\boldsymbol{{speed}}\:\boldsymbol{{around}}\:\boldsymbol{{the}}\:\boldsymbol{{sun}}\:\boldsymbol{{both}} \\ $$$$\boldsymbol{{in}}\:\boldsymbol{{this}}\:\boldsymbol{{case}}\:\boldsymbol{{are}}\:\boldsymbol{{same}}\:\boldsymbol{{as}}\:\boldsymbol{{earth}}. \\ $$$$\boldsymbol{{so}}\:\boldsymbol{{from}}\:\boldsymbol{{this}}\:\boldsymbol{{assumtion}}\:\boldsymbol{{you}}\:\boldsymbol{{also}} \\ $$$$\boldsymbol{{at}}\:\boldsymbol{{rest}}\:\boldsymbol{{for}}\:\boldsymbol{{the}}\:\boldsymbol{{prime}}\:\boldsymbol{{observer}}\:\boldsymbol{{who}}\:\boldsymbol{{is}} \\ $$$$\boldsymbol{{watching}}\:\boldsymbol{{over}}\:\boldsymbol{{you}}. \\ $$$$\boldsymbol{{so}}\:\boldsymbol{{v}}_{\boldsymbol{{rel}}} =\mathrm{0}\:\boldsymbol{{so}}\:\boldsymbol{\lambda}\Rightarrow\infty..\boldsymbol{{worthless}}!! \\ $$$$\boldsymbol{{for}}\:\boldsymbol{{simplification}}\:\boldsymbol{{you}}\:\boldsymbol{{can}}\: \\ $$$$\boldsymbol{{consider}}\:\boldsymbol{{a}}\:\boldsymbol{{frame}}\:\boldsymbol{{of}}\:\boldsymbol{{reference}} \\ $$$$\boldsymbol{{like}}\:\boldsymbol{{a}}\:\boldsymbol{{geostationary}}\:\boldsymbol{{satelite}}. \\ $$
Commented by prakash jain last updated on 23/Jun/20
$$\mathrm{The}\:\mathrm{laws}\:\mathrm{of}\:\mathrm{quantum}\:\mathrm{physics}\:\mathrm{apply} \\ $$$$\mathrm{to}\:\mathrm{all}\:\mathrm{objects}\:\mathrm{regardless}\:\mathrm{of}\:\mathrm{mass}. \\ $$
Commented by smridha last updated on 23/Jun/20
$$\boldsymbol{{but}}\:\boldsymbol{{it}}'\boldsymbol{{s}}\:\boldsymbol{{not}}\:\boldsymbol{{logical}}\:\boldsymbol{{to}}\:\boldsymbol{{use}} \\ $$$$\boldsymbol{{because}}\:\boldsymbol{{the}}\:\boldsymbol{{result}}\:\boldsymbol{{is}}\:\:\boldsymbol{{very}} \\ $$$$\boldsymbol{{negligible}}…\boldsymbol{{therefore}}\: \\ $$$$\boldsymbol{{physicists}}\:\boldsymbol{{say}}\:\boldsymbol{{classical}}\:\boldsymbol{{mechanics}} \\ $$$$\boldsymbol{{is}}\:\boldsymbol{{the}}\:\boldsymbol{{approximation}}\:\boldsymbol{{of}}\:\boldsymbol{{quantum}} \\ $$$$\boldsymbol{{mechanics}}….\boldsymbol{{if}}\:\boldsymbol{{the}}\:\boldsymbol{{result}}\:\boldsymbol{{is}}\: \\ $$$$\boldsymbol{{same}}\:\boldsymbol{{then}}\:\boldsymbol{{there}}\:\boldsymbol{{is}}\:\boldsymbol{{no}}\:\boldsymbol{{cause}}\:\boldsymbol{{to}} \\ $$$$\boldsymbol{{devolope}}\:\boldsymbol{{quantum}}\:\boldsymbol{{mechanics}}.. \\ $$$$\boldsymbol{{you}}\:\boldsymbol{{should}}\:\boldsymbol{{aware}}\:\boldsymbol{{of}}\:\boldsymbol{{that}}\:\boldsymbol{{in}} \\ $$$$\boldsymbol{{which}}\:\boldsymbol{{context}}\:\boldsymbol{{which}}\:\boldsymbol{{formula}} \\ $$$$\boldsymbol{{do}}\:\boldsymbol{{you}}\:\boldsymbol{{use}}\:\boldsymbol{{or}}\:\boldsymbol{{not}}\:\boldsymbol{{able}}\:\boldsymbol{{to}}\:\boldsymbol{{use}}.. \\ $$$$\boldsymbol{{classical}}\:\boldsymbol{{and}}\:\boldsymbol{{quantum}}\:\boldsymbol{{both}} \\ $$$$\boldsymbol{{are}}\:\boldsymbol{{important}}…{phy}\boldsymbol{{sicists}}\:\boldsymbol{{do}}\:\boldsymbol{{not}} \\ $$$$\boldsymbol{{happy}}\:\boldsymbol{{with}}\:\boldsymbol{{some}}\:\boldsymbol{{mathematical}} \\ $$$$\boldsymbol{{result}}\:\boldsymbol{{but}}\:\boldsymbol{{the}}\:\boldsymbol{{significant}}\: \\ $$$$\boldsymbol{{mathematical}}\:\boldsymbol{{result}}\:\boldsymbol{{and}}\:\boldsymbol{{so}} \\ $$$$\boldsymbol{{they}}\:\boldsymbol{{give}}\:\boldsymbol{{same}}\:\boldsymbol{{pr}}{i}\boldsymbol{{ority}}\:\boldsymbol{{to}}\:\boldsymbol{{both}} \\ $$$$\boldsymbol{{mechanics}}… \\ $$
Commented by prakash jain last updated on 23/Jun/20
$$\mathrm{100\%}\:\mathrm{agree}\:\mathrm{with}\:\mathrm{you}. \\ $$