A gas absorbs a photon of 355 nm and emits at two wavelengths. If one of the emissions is at 680 nm, the other is at:

1. 1035 nm

2. 325 nm

3. 743 nm

4. 518 nm

Subtopic:  Planck's Theory |
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The energy required to break one mole of CI–Cl bonds in Cl2 is 242 kJmol−1. The wavelength of light capable of breaking a single Cl–Cl bond is:

1. 494 nm

2. 594 nm

3. 640 nm

4. 700 nm

Subtopic:  Planck's Theory |
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If the work function of a metal is 6.63 × 10–19J, the maximum wavelength of the photon required to remove a photoelectron from the metal is :
(Given h = 6.63 × 10–34 J sec)

1. 280 nm 
2. 310 nm
3. 300 nm
4. 290 nm
Subtopic:  Planck's Theory |
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lf the work function of a metal is \(\mathrm{6.63 × 10^{–19}~ J,}\) the maximum wavelength of the photon required to remove a photoelectron from the metal is ______ nm. (Nearest integer)
\([\text{Given} : \mathrm{h}=6.63 \times 10^{-34} \mathrm{~J} \mathrm{~s}, \text{and} \left.\mathrm{c}=3 \times 10^8 \mathrm{~m} \mathrm{~s}^{-1}\right]\)

1. 100nm
2. 400nm
3. 300nm
4. 479nm
Subtopic:  Planck's Theory |
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The de Broglie wavelength of an electron and a neutron become equal when the velocity of the electron is x times the velocity of the neutron. The value of x is:

[Given: Mass of electron is \(9.1 \times 10^{-31} \text {kg}\) and mass of neutron is \( 1.6 \times 10^{-27} \mathrm{~kg} \)]

1. 1758 2. 3054
3. 1239 4. 6215
Subtopic:  Planck's Theory |
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A metal surface is exposed to 500 nm radiation. The threshold frequency of the metal for photoelectric current is \(4.3\times10^{14}~Hz.\)If the velocity of ejected electron is \(x\times10^5~ms^{-1}.\) Find \(x\): (Nearest integer)
[Use: \(\left.\mathrm{h}=6.63 \times 10^{-34} \mathrm{Js}, \mathrm{m}_{\mathrm{e}}=9.0 \times 10^{-31} \mathrm{Kg}\right]\)

1. Five (5)
2. Eight (8)
3. Twelve (12)
4. Two (2)
Subtopic:  Planck's Theory |
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