Q. No.The number of protons, neutrons and electrons in \( _{71}^{175}Lu\) respectively, are:
1. 104, 71 and 71
2. 71, 71 and 104
3. 175, 104 and 71
4. 71, 104 and 71
| 1. | \(\mathrm {^{56}Fe }\) | 2. | \({ }^{57} \mathrm{Fe}\) |
| 3. | \({ }^{57} \mathrm{Co}\) | 4. | \({ }^{60} \mathrm{Co}\) |
A monochromatic infrared range finder of power 1milli watt emits photons with wavelength 1000 nm in 0.1 second. The number of photons emitted in 0.1 second is:
(Given: h = \(6.626 \times 10^{-34} J~s\) , c = \(3 \times 10^8 m~s^{-1}, \) Avogadro number = \(6.022 \times 10^{23}\))
1. \(30 \times 10^{37}\)
2. \(5 \times 10^{14} \)
3. \(30 \times 10^{34} \)
4. \(5 \times 10^{11} \)
A particular station of All India Radio, New Delhi, broadcasts on a frequency of 1,368 kHz (kilohertz). The wavelength of the electromagnetic radiation emitted by the transmitter is: [speed of light, ]
| 1. | 2192 m | 2. | 21.92 cm |
| 3. | 219.3 m | 4. | 219.2 m |
Calculate the energy corresponding to light of wavelength 45 nm:
(Planck's constant h = 6.63 × 10–34 Js & speed of light c = 3 × 108 ms–1)
1. 6.67 x 1015 J
2. 6.67 x 1011 J
3. 4.42 x 10-15 J
4. 4.42 x 10-18 J
(GivenL: h = 6.626 × 10–34 Js, c = 3 × 108 ms–1, NA = 6.022 × 1023 mol–1)
1. 2.31 × 106 J mol–1
2. 3.84 × 104 J mol–1
3. 3.84 × 10–19 J mol–1
4. 2.31 × 105 J mol–1
transitions, respectively, is
| 1. | \(\dfrac{1}{9}\) | 2. | \(\dfrac{1}{4}\) |
| 3. | \(\dfrac{1}{36}\) | 4. | \(\dfrac{1}{16}\) |
| 1. | 158.7 Å | 2. | 158.7 pm |
| 3. | 15.87 pm | 4. | 1.587 pm |
| Statement I: | The Balmer spectral line for H atom with lowest energy appears at \(\dfrac 5{36}\mathrm{ R_H~ cm^{-1}}\) (\(\mathrm{R_H}\) = Rydberg constant) |
| Statement II: | When the temperature of a black body increases, the maxima of the curve (intensity versus wavelength) shifts towards shorter wavelength. |
| 1. | Statement I is correct and Statement II is incorrect. |
| 2. | Statement I is incorrect and Statement II is correct. |
| 3. | Both Statement I and Statement II are correct. |
| 4. | Both Statement I and Statement II are incorrect. |
| Statement I: | The energy of the \(\mathrm{He}^{+}\) ion in \(n=2\) state is same as the energy of H atom in \(n=1\) state. |
| Statement II: | It is possible to determine simultaneously the exact position and exact momentum of an electron in \(\mathrm{H}\) atom. |
| 1. | Both Statement I and Statement II are true |
| 2. | Both Statement I and Statement II are false |
| 3. | Statement I is true and Statement II is false |
| 4. | Statement I is false, and Statement II is true |
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