The energy of the photon with a frequency of 3 × 10¹⁵ Hz is:

1. 1.988 × ${10}^{-18}$ J
2. 1.588 × ${10}^{-18}$ J
3. 1.288 × ${10}^{-18}$ J
4. 2.988 × ${10}^{-18}$ J

The correct arrangement of the following electromagnetic spectrum in the increasing order of frequency is:

The neon gas emits radiation of 616 nm. The number of quanta that are present in 2 J of energy is:

1. \(6.2 \times 10^{-18} \)
2. \(5.6 \times 10^{17} \)
3. \(6.2 \times 10^{18} \)
4. \(32.2 \times 10^{-20}\)