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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 4401. |
Given : `S_((s))+(3)/(2)O_(2(g))rarrSO_(3(g)+2X Kcal` `SO_(2(s))+(1)/(2)O_(2(g))rarrSO_(3(g)+Y Kcal` The heat of formation of `SO_(2)` is `:-`A. `Y-2X`B. `X-Y`C. `x+Y`D. `2x+y` |
| Answer» Correct Answer - A | |
| 4402. |
At 298 K, the vapour pressure of pure benzene, C6H6 is 0.256 bar and the vapourpressure of pure tolueneC6H5CH3 is 0.0925 bar. Two mixtures were prepared as follows:0 7.8 g of C6H6 + 9.2 g of toluene(i) 3.9 g of C6H6 + 13.8 g of tolueneThe following questions are multiple choice questions. Choose the mostappropriate answer:0) The total vapour pressure (bar) of solution 1 is(a)(b)(C)0.1280.1740.198(d)0.258(in Which of the given solutions have higher vapour pressure?(a) I(b)Il(c) Both have equal vapour(d) Cannot bepressurepredicted(ill) Mole fraction of benzene in vapour phase in solution 1 is(a)0.128(b)(c)(d)0.1740.7340.266(iv) Solution I is an example of a/an(a) ideal solution(c) non-ideal solution with negativedeviation(b) non-ideal solution with positive dev(d) can't be predicted |
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Answer» Given, \(P^0_{C_6H_6} = 0.256\) bar \(P^0_{C_7H_8} = 0.0925 \) bar molecular weight of C6H6 = 78 g/mol and molecular weight of C7H8 = 92 g/mol. For Solution - 1 Mole fraction of benzene in solution = \(\cfrac{\frac{7.8}{78}}{\frac{7.8}{78}+ \frac{9.2}{92}}\) \(= \frac{0.1}{0.1 + 0.1}\) \(=\frac12\) \(= 0.5\) ∴ Mole fraction of toluene = 1 - 0.5 = 0.5 For Solution - 2 Mole fraction of benzene = \(\cfrac{\frac{3.9}{78}}{\frac{3.9}{78}+ \frac{13.8}{92}}\) \(= \frac{0.05}{0.05 + 0.15}\) \(= 0.25\) ∴ Mole fraction of toluene = 1 - 0.25 = 0.75 ♦ Total vapour pressure in solution 1 \(P_{total} = (X_{benzene}\times P^0_{benzene}) + (X_{toluene} \times P^0_{toluene})\) \(= 0.5 \times 0.256 + 0.5 \times 0.0925\) \(P_{total} = 0.174\) bar ♦ Total vapour pressure in solution - 2 \(P_2 = 0.25 \times 0.256 + 0.75 \times 0.0925\) \(= 0.133\) bar ♦ Solution (1) has higher vapour pressure than Solution (2). ♦ Mole fraction of benzene in vapour phase in Solution (1). ♦ Mole fraction of benzene in vapour phase in solution (1) \(Y_{benzene} = \frac{X_{benzene}\times P^0_{benzene}}{P_{total}}\) \(= \frac{0.5 \times 0.256}{0.174}\) \(Y_{benzene} = 0.734\) ♦ Solution (1) is an example of a ideal solution because toluene and bezene are much similar in polarity they follow Roult's Law. |
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| 4403. |
100 g of an ideal gas is kept in a cylinder of 416 L volume at 27°C under 1.5 bar pressure. The molar mass of the gas is ______ g mol–1 . (Nearest integer) (Given : R = 0.083 L bar K–1 mol–1 ) |
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Answer» Correct answer is 3.99 1.5 x 416 = 100/M x 0.083 x 300 M = 3.99 |
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| 4404. |
An ideal gas A is present in a closed rigid container at 27°C and 38 atm pressure, then find pressure of gas at 45°C. |
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Answer» At constant volume and mole \(\frac{P_1}{T_1} = \frac{P_2}{T_2}\) \(\frac{38}{300} = \frac{P_2}{318}\) \(P_2 = \left(\frac{38}{300}\right)318 \) \(P_2 = 40.28\) |
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| 4405. |
The reaction of NO with N2O4 at 250 K gives: (1) N2O5 (2) NO2(3) N2O(4) N2O3(4) N2O3 |
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Answer» Correct answer is (4) N2O3 2 NO + N2O4 \(\overset {250K}{\longrightarrow}\) 2N2O3 (blue solid) |
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| 4406. |
Calculate the ΔH of the following reaction: CO2(g) + H2(g)O -> H2CO3(g) if the standard values of ΔHf are as follows: CO2(g) : -393.509 KJ/mol, H2O(g): – 241.83 KJ/mol, and H2CO3(g) : – 275.2 KJ/mol.(a) +360.139 KJ(b) +350.129 KJ(c) – 360.139 KJ(d) -350.129 KJ |
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Answer» The correct choice is (a) +360.139 KJ Easy explanation: ΔH° = ƩΔvpΔH°f (products) – ƩΔvrΔH°f (reactants) so this means that you add up the sum of the ΔH’s of the products and subtract away the ΔH of the products: (- 275.2 KJ) – (-393.509 KJ + -241.83KJ) = (-275.2) – (-635.339) = + 360.139 KJ. |
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| 4407. |
एक किसान 6 घंटे प्रतिदिन काम करके एक खेत को 18 दिनों में जोत सकता है तो उसी काम को 12 दिनों में समाप्त करने के लिए किसान को कितने घंटे प्रतिदिन काम करना पड़ेगा ?A. 7 hrsB. 9 hrsC. 11 hrsD. 13 hrs |
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Answer» Correct Answer - b (b) Let woker work in n hours farmer worker `6_(hrs ) xx18 _(days) = 12 _(days) xx n_(hrs)` `6xx(18)/(12)=n` n= 9 hrs |
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| 4408. |
After a road accident, a person lost his memory for a few days. In which part of his brain got injured? |
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Answer» The part of his brain got injured is Cerebrum. |
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| 4409. |
Tidal Volume and Expiratory Reserve Volume of an athlete is 500 mL and 1000 mL, respectively. What will be his Expiratory Capacity if the Residual Volume is 1200 mL? (1) 1500 mL (2) 1700 mL (3) 2200 mL (4) 2700 mL |
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Answer» Correct option: (1) 1500 mL Explanation: Tidal Volume = 500 ml Expiratory Reserve Volume = 1000 ml Expiratory Capacity = TV + ERV = 500 + 1000 = 1500 ml |
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| 4410. |
The vibrations produced in the ear drum are transmitted through the ear ossicles to the fluid filled inner ear via -A. Oval windowB. Both oval and round windowC. Round windowD. Helicotrema |
| Answer» Correct Answer - A | |
| 4411. |
Why certain person feel ear pain as they goes higher altitudes? |
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Answer» When we goes higher altitudes, the atmospheric pressure decreases. This creates low pressure on one side of the eardrum to cause pain. |
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| 4412. |
The tube that connects the middle ear to the pharynx? What is its function? |
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Answer» Eustachian tube. It helps to regulate the pressure inside the middle ear. |
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| 4413. |
विनम्रता मनुष्य का अनुभव है इस पर अपने विचार व्यक्त कीजिए |
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Answer» विनम्रता मनुष्य के व्यक्तित्व का आभूषण है। इसके माध्यम से हमारा व्यक्तित्व खूबसूरत बनता है, क्योंकि विनम्र होकर ही हम पात्रता अर्जित कर सकते हैं। विनम्र होकर हम ग्रहण करना सीखते हैं और विनम्रता के कारण ही हम दूसरों से जुड़ पाते हैं। भारतीय संस्कृति में इसी विनम्रता को व्यक्त करने के लिए प्रणाम और अभिवादन करने की परंपरा है। हमारे धर्मग्रंथों का एक मूलमंत्र है: जो नम्र होकर झुकते हैं, वही ऊपर उठते हैं। विनम्रता न केवल हमारे व्यक्तित्व में निखार लाती है, बल्कि कई बार सफलता का कारण भी बनती है। विनम्रता के कारण जो सम्मान मिलता है, उसका एक अलग महत्व है। मन की कोमलता और व्यवहार में विनम्रता एक बड़ी शक्ति है। इस शक्ति के कारण ही हम खुद पर और अन्यों पर काबू पा सकते हैं। इससे स्वाभाविक है कि जब हम खुद पर नियंत्रण पा लेते हैं तो इस कला से हम किसी को भी अपने नियंत्रण में कर सकते हैं, और खुद को व अन्यों को सुख दे सकते हैं। विनम्रता मानव का श्रेष्ठ आभूषण है। विनम्रता हमारे दैनिक जीवन के व्यवहार का एक ऐसा मजबूत कवच है जिसको पहनकर हम किसी भी तरह की नकारात्मकता को अपने ऊपर हावी नहीं होने दे सकते हैं। विनम्रता अपनाने से मनुष्य के अंदर सद्गुणों का विकास होता है। विनम्र व्यक्ति शांत होते हैं अतः विनम्रता शांति का प्रतीक है। जो व्यक्ति स्वभाव से शांत होगा। वही विनम्र बन सकता है। संसार में बड़े-बड़े जितने भी महापुरुष हुए हैं। उन्होंने अपने व्यवहार में विनम्रता को अपनाया तभी वो उच्च स्तर पर पहुंच पाए। अगर वह अपने स्वभाव में विनम्रता नहीं लाते तो शायद हम उनका नाम इतने आदर पूर्वक नहीं लेते। विनम्र व्यक्ति को सब पसंद करते हैं, गुस्सैल और अहंकारी व्यक्ति से सब दूर भागते हैं। इतिहास में ऐसे अनेक उदाहरण भी हैं, जिन्होंने विनम्रता का परित्याग कर दिया। जिनमें अहंकार था और ये अहंकार उनके नाश का कारण बना। उदाहरण के लिए रावण, कंस, हिरण्यकश्यप, हिटलर आदि सब अहंकार के प्रतिनिधि थे। उन्होंने अपनी विनम्रता का त्याग कर दिया और अहंकार का दामन थाम लिया। जिसके कारण उनका नाश हुआ। यदि कोई व्यक्ति प्रसिद्ध है, धनवान है, योग्य है, किसी विशेष क्षेत्र में सक्रिय है और उसके बाद विनम्र भी है तो कहना ही क्या। यह तो सोने पर सुहागा जैसी बात हो जाएगी। विनम्रता हमारे गुणों में चार चांद लगाती है। विनम्रता हमारे स्वभाव के लिए एक श्रंगार के समान है। जो हमारे स्वभाव और आचरण को निखार देती है। विनम्रता अहंकार का नाश करती है, और जहां अहंकार का नाश होता है वही ज्ञान की उत्पत्ति होती है। अतः लिए विनम्रता ज्ञान का द्वार है. |
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| 4414. |
तुम भारत, हम भारतीय हैं, तू माता हम बेटे किसकी हिम्मत है कि तुम्हें दुस्ता दृष्टि से देखे। ओ माता, तुम एक अरब से अधिक भुजाओं वाली सबकी रक्षा में तुम सक्षम हो अदम्य बलशाली। भाषा, देश, प्रदेश भिन्न है, फिर भी भाई-भाई, भारत की साझी संस्कृति में पलते भारतवासी सुदिनों में हम एक साथ हँसते, गाते, सोते हैं, दुर्दिन में भी साथ-साथ जागते, पौरुष धोते हैं। तुम हो शस्य श्यामला, खेतों में तुम लहराती हो, प्रकृति प्राणमयी साम-गानमयी, तुम न किसे भाती हो। तुम न अगर होती तो धरती वसुधा क्यों कहलाती? गंगा कहाँ बहा करती, गीता क्यों गाई जाती? |
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Answer» प्रश्न- (क) साझी संस्कृति का क्या भाव है? (ख) भारत को अदम्य बलशाली क्यों कहा गया है? (ग) सुख-दुःख के दिनों में भारतीयों का परस्पर सहयोग कैसा होता है? (घ) साम-गानमयी का क्या तात्पर्य है? (ङ) ‘ओ माता, तुम एक अर्ब से अधिक भुजाओं वाली’ में कौन-सा अलंकार है? उत्तर- (क) भाषा, वेश, प्रदेश भिन्न होते हुए भी सभी के सुख-दुःख एक हैं। (ख) भारतीय की एक अर्ब से अधिक जनता अपनी मजबूत भुजाओं से सबकी सुरक्षा करने में समर्थ है। (ग) भारतीयों का व्यवहार आपसी सहयोग और अपनेपन से भरा है सब संग-संग हँसते-गाते हैं और संग-संग कठिनाइयों से जूझते हैं। (घ) सुमधुर संगीत से युक्त। (ङ) रूपक। |
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| 4415. |
Taking one mole of `N_(2(g))` and excess of `H_(2)(g)`, under suitable conditions, formation of `NH_(3)` is completed when `NH_(3)(g)` has mole fraction of `0.5`, The initial moles of `H_(2)` are? |
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Answer» Correct Answer - 5 `underset (0) underset (1) (N_(2))+ underset(a-3) underset(a) (3H_(2))tounderset(2) underset(0) (2NH_(3))` |
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| 4416. |
Reaction A `to` B carried out inside a container.Concentration varies as `C_t=a+bt`.Rate of reaction can be expressed in term of pressure at temp T=300 K, Take b=4, `R=1/12` atm `mol^(-1) k^(-1)` Give your Answer divide by 10. |
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Answer» Correct Answer - 10 `AtoB` `C_1=a+bt` p=(a+bt)RT `(dp)/(dt)=dRT " " =4xx1/12xx300=100 "atm" sec ^(-1)` |
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| 4417. |
For a binary liquid solution of A and B. `P_A^0`=pure vapour pressure of A . `P_B^0`=pure vapour pressure of B. `X_A`=mole fraction of A in liquid phase.`Y_A`=mole fraction of A in vapour phase. `{:("Column I","Column II"),((A)P_A^0gtP_B^0"[Ideal liquid solution]",(p)X_A=Y_A),((B)"Azeotropic mixture",(q)X_AltY_A),(( C)"Equimolar ideal mixture of A & B with "P_A^0ltP_B^0,(r)X_BltY_B),((D)"Equimolar ideal mixture of A & B with "P_A^0=P_B^0,(s)Y_BgtY_A),(,(t)X_B=Y_B):}` |
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Answer» Correct Answer - A-q ; B-p,t ; C-r,s ; D-p (A)`P_A^0gt P_B^0` means A is more volatile than B and therefore A will be richer in vapour phase , [or `Y_A=X_A(P_A^0)/P_T`] (B)For azeotropes composition of vapour phase and liquid phase is same (C )For `P_A^0 lt P_B^@ ,X_B lt Y_B and Y_B gt Y_A` for an equimolar ratio. (D) For `P_A^0=P_B^0,X_A=Y_A` for an equimolar ratio. |
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| 4418. |
The force exerted on a magnetic dipole as it moves with velocity Vector v through a Stern-Gerlach apparatus is: A. proportional to v B. proportional to 1/v C. zero D. proportional to v2 E. independent of v |
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Answer» E. independent of v |
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| 4419. |
The group of atoms at the beginning of periods of the periodic table are called: A. alkali metal atoms B. rare earth atomsC. transition metal atoms D. alkaline atoms E. inert gas atoms |
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Answer» A. alkali metal atoms |
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| 4420. |
The equivalent capacity between A and B in the given figure is:(a) 6 μF(b) 18 μF(c) 9 μF(d) 1/9 μF |
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Answer» Correct answer is (c) 9 μF |
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| 4421. |
To observe the Zeeman effect one uses: A. a strong uniform magnetic field B. a strong non-uniform magnetic field C. a strong uniform electric field D. a strong non-uniform electric field E. mutually perpendicular electric and magnetic fields |
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Answer» B. a strong non-uniform magnetic field |
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| 4422. |
Characteristic K x-radiation of an element occurs when: A. the incident electron is absorbed by a target nucleus B. the incident electron is scattered by a target atom without an energy loss C. an electron is ejected from an outer shell of a target atom D. an electron in a target atom makes a transition to the lowest energy state E. the incident electron goes into the lowest energy state |
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Answer» D. an electron in a target atom makes a transition to the lowest energy state |
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| 4423. |
Two different electron beams are incident on two different targets and both produce x rays. The cutoff wavelength for target 1 is shorter than the cutoff wavelength for target 2. We can conclude that: A. target 2 has a higher atomic number than target 1 B. target 2 has a lower atomic number than target 1 C. the electrons in beam 1 have greater kinetic energy than those in beam 2 D. the electrons in beam 1 have less kinetic energy than those in beam 2 E. target 1 is thicker than target 2 |
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Answer» C. the electrons in beam 1 have greater kinetic energy than those in beam 2 |
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| 4424. |
The most energetic photon in a continuous x-ray spectrum has an energy approximately equal to: A. the energy of all the electrons in a target atom B. the kinetic energy of an incident-beam electron C. the rest energy, mc2, of an electron D. the total energy of a K-electron in the target atom E. the kinetic energy of a K-electron in the target atom |
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Answer» B. the kinetic energy of an incident-beam electron |
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| 4425. |
A laser must be pumped to achieve: A. a metas table state B. fast response C. stimulated emission D. population inversion E. the same wavelength for all photons |
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Answer» D. population inversion |
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| 4426. |
In connection with x-ray emission the symbol Kα refers to: A. an alpha particle radiation B. an effect of the dielectric constant on energy levelsC. x-ray radiation from potassium D. x-ray radiation associated with an electron going from n = ∞ to n = 1 E. x-ray radiation associated with an electron going from n = 2 to n = 1 |
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Answer» E. x-ray radiation associated with an electron going from n = 2 to n = 1 |
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| 4427. |
Radiation with the minimum wavelength as well as the K x-ray lines are detected for a certain target. The energy of the incident electrons is then doubled, with the result that A. the minimum wavelength increases and the wavelengths of the K lines remain the same B. the minimum wavelength decreases and the wavelengths of the K lines remain the same C. the minimum wavelength and the wavelengths of the K lines all increase D. the minimum wavelength and the wavelengths of the K lines all decrease E. the minimum wavelength increases and the wavelengths of the K lines all decrease |
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Answer» B. the minimum wavelength decreases and the wavelengths of the K lines remain the same |
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| 4428. |
A photon with the smallest wavelength in the continuous z-ray spectrum is emitted when: A. an electron is knocked from a K shell B. a valence electron is knocked from the atom C. the incident electron becomes bound to the atom D. the atom has the greatest recoil energy E. the incident electron loses all its energy in a single decelerating event |
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Answer» E. the incident electron loses all its energy in a single decelerating event |
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| 4429. |
The group of atoms at the ends of periods of the periodic table are called: A. alkali metals B. rare earths C. transition metal atoms D. alkaline atoms E. inert gas atoms |
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Answer» E. inert gas atoms |
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| 4430. |
In a Moseley graph: A. the x-ray frequency is plotted as a function of atomic number B. the square of the x-ray frequency is plotted as a function of atomic number C. the square root of the x-ray frequency is plotted as a function of atomic number D. the x-ray frequency is plotted as a function of the square root of atomic number E. the square root of the x-ray frequency is plotted as a function of atomic mass |
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Answer» C. the square root of the x-ray frequency is plotted as a function of atomic number |
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| 4431. |
In connection with x-ray emission the symbol Lβ refers to: A. a beta particle radiation B. an atomic state of angular momentum h/2π C. the inductance associated with an orbiting electron D. x-radiation associated with an electron going from n = 4 to n = 2 E. none of the above |
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Answer» D. x-radiation associated with an electron going from n = 4 to n = 2 |
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| 4432. |
When a lithium atom in its ground state is made from a helium atom by adding a proton (and neutron) to the nucleus and an electron outside, the electron goes into an n = 2, f = 0 state rather than an n = 3, f = 0 state. This is an indication that electrons: A. obey the Pauli exclusion principle B. obey the minimum energy principle C. undergo the Zeeman effect D. are diffracted E. and protons are interchangeable |
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Answer» B. obey the minimum energy principle |
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| 4433. |
The torque acting on electric dipole of dipole moment vector p placed in electric field of intensity vector E is:(a) (vector P x E)(b) (vector P.E) (c) PE(d) (vector P/E) |
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Answer» Correct answer is (a) (vector P x E) |
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| 4434. |
In calculating the x-ray energy levels the effective charge of the nucleus is taken to be Z − b, where Z is the atomic number. The parameter b enters because: A. an electron is removed from the inner shell B. a proton is removed from the nucleus C. the quantum mechanical force between two charges is less than the classical force D. the nucleus is screened by electrons E. the Pauli exclusion principle must be obeyed |
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Answer» D. the nucleus is screened by electrons |
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| 4435. |
For any atom other than hydrogen and helium all electrons in the same shell have: A. the same energy B. the same magnitude of angular momentum C. the same magnetic quantum number D. the same spin quantum number E. none of the above |
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Answer» E. none of the above |
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| 4436. |
In a laser: A. excited atoms are stimulated to emit photons by radiation external to the laser B. the transitions for laser emission are directly to the ground state C. the states which give rise to laser emission are usually very unstable states that decay rapidly D. the state in which an atom is initially excited is never between two states that are involved in the stimulated emission E. a minimum of two energy levels are required. |
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Answer» D. the state in which an atom is initially excited is never between two states that are involved in the stimulated emission |
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| 4437. |
The effective charge acting on a single valence electron outside a closed shell is about Ne, where N is: A. the atomic number of the nucleus B. the atomic mass of the atom C. usually between 1 and 3 D. half the atomic number E. less than 1 |
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Answer» C. usually between 1 and 3 |
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| 4438. |
The possible values for the magnetic quantum number ms of an electron in an atom: A. depend on n B. depend on f C. depend on both n and f D. depend on whether there is an external magnetic field present E. are ±1/2 |
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Answer» E. are ± 1/2 |
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| 4439. |
Which of the following is essential for laser action to occur between two energy levels of an atom? A. the lower level is metastable B. there are more atoms the upper level than in the lower level C. there are more atoms in the lower level than in the upper level D. the lower level is the ground state E. the lasing material is a gas |
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Answer» B. there are more atoms the upper level than in the lower level |
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| 4440. |
No state in an atom can be occupied by more than one electron. This is most closely related to: A. the wave nature of matter B. the finite value for the speed of light C. the Bohr magneton D. the Pauli exclusion principle E. the Einstein-de Haas effect |
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Answer» D. the Pauli exclusion principle |
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| 4441. |
The electron states that constitute a single subshell for an atom all have: A. only the same value of n B. only the same value of f C. only the same value of n and the same value of f D. only the same value of f and the same value of mf E. the same set of all four quantum numbers |
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Answer» A. the same value of n |
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| 4442. |
According to the theory of relativity: A. moving clocks run fast B. energy is not conserved in high speed collisions C. the speed of light must be measured relative to the ether D. momentum is not conserved in high speed collisions E. none of the above are true |
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Answer» E. none of the above are true |
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| 4443. |
Two events occur simultaneously on the x axis of reference frame S, one at x = −a and the other at x = +a. According to an observer moving in the positive x direction: A. the event at x = +a occurs first B. the event at x = −a occurs first C. either event might occur first, depending on the value of a and the observer’s speed D. the events are simultaneous E. none of the above |
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Answer» A. the event at x = +a occurs first |
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| 4444. |
The magnitude of the momentum of a particle can never exceed: A. mc, where m is its mass B. E/c, where E is its total energy C. K/c, where K is its kinetic energy D. none of the above, but there is an upper limit E. none of the above; there is no upper limit |
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Answer» B. E/c, where E is its total energy |
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| 4445. |
Two events occur simultaneously at separated points on the y axis of reference frame S. According to an observer moving in the positive x direction: A. the event with the greater y coordinate occurs first B. the event with the greater y coordinate occurs last C. either event might occur first, depending on the observer’s speed D. the events are simultaneous E. none of the above |
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Answer» D. the events are simultaneous |
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| 4446. |
Two events occur on the x axis separated in time by ∆t and in space by ∆x. A reference frame, traveling at less than the speed of light, in which the two events occur at the same coordinate: A. exists no matter what the values of ∆x and ∆t B. exists only if ∆x/∆tc D. exists only if ∆x/∆t = c E. does not exist under any condition |
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Answer» B. exists only if ∆x/∆t<c |
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| 4447. |
A measurement of the length of an object that is moving relative to the laboratory consists of noting the coordinates of the front and back: A. at different times according to clocks at rest in the laboratory B. at the same time according to clocks that move with the object C. at the same time according to clocks at rest in the laboratory D. at the same time according to clocks at rest with respect to the fixed stars E. none of the above |
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Answer» C. at the same time according to clocks at rest in the laboratory |
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| 4448. |
A train traveling very fast (v = 0.6c) has an engineer (E) at the front, a guard (G) at the rear, and an observer (SI ) exactly half way between them. Both E and G are equipped with yellow signaling lamps. The train passes a station, closely observed by the station master (S). Both E and G use their lamps to send signals. According to both S and SI these signals arrive simultaneously at the instant SI is passing S. According to SI : A. E and G sent their signals simultaneously from different distances B. G sent his signal before E and from farther away C. G sent his signal before E but was the same distance away D. E sent his signal before G and from farther away E. none of the above |
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Answer» E. none of the above |
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| 4449. |
As we watch, a spaceship passes us in time ∆t. The crew of the spaceship measures the passage time and finds it to be ∆tI . Which of the following statements is true? A. ∆t is the proper time for the passage and it is smaller than ∆tI B. ∆t is the proper time for the passage and it is greater than ∆t I C. ∆tI is the proper time for the passage and it is smaller than ∆t D. ∆t I is the proper time for the passage and it is greater than ∆t E. None of the above statements are true. |
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Answer» C. ∆tI is the proper time for the passage and it is smaller than ∆t |
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| 4450. |
A console lamp in the cabin of a spaceship appears green when the ship and observer are both at rest on Earth. When the ship is moving at 0.90c away from Earth, passengers on board see: A. nothing (the frequency is too high to be seen) B. nothing (the frequency is too low to be seen) C. a red lamp D. a violet lamp E. a green lamp |
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Answer» E. a green lamp |
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