A photon detector receives a total energy of \(3.15 \times 10^{-18}\) J from radiation with a wavelength of 600 nm. How many photons are received by the detector?
The energy associated with the emission of 2.5 × 1015 photons in 2 nanoseconds is:
1. \(8 . 28\) \(\times\) \(10^{- 10}\) \(J\)
2. \(8 . 24\) \(\times\) \(10^{11}\) \(J\)
3. \(7 . 12\) \(\times\) \(10^{- 11}\) \(J\)
4. \(2 . 12\) \(\times\) \(10^{-10}\)\(J\)
Emission transitions in the Paschen series end at orbit n = 3 and start from orbit n and can be represented as v = 3.29 × 1015 (Hz) . The value of n if the transition is observed at 1285 nm is :
1. | 6 | 2. | 5 |
3. | 8 | 4. | 9 |
If the velocity of the electron is 1.6 × 106 . The de Broglie wavelength associated with this electron is:
The characteristic velocity associated with a neutron that has a wavelength of 800 pm is :
1. | 496 m s–1 | 2. | 567 m s–1 |
3. | 494 cm s–1 | 4. | 501 m s–1 |
The velocity associated with a proton moving at a potential difference of 1000 V is 4.37 × 105 ms–1. If the hockey ball of mass 0.1 kg is moving with this velocity, then the wavelength associated with this velocity would be:
The ratio of the wavelengths of the last lines of the Balmer to Lyman series is
1. | 4:1 | 2. | 27:5 |
3. | 3:1 | 4. | 9:4 |
A nitrogen laser produces radiation at a wavelength of 337.1 nm. If the number of photons emitted per second is 5.6 × 1024,
the power of the laser is:
An ion with a mass number of 56 contains 3 units of positive charge and 30.4% more neutrons than electrons. The symbol of the ion is :
An element with a mass number of 81 contains 31.7% more neutrons as compared to protons. The atomic symbol of the element would be :