What is the value of Planck's constant (h)?

Planck's constant (h) is a fundamental constant in quantum mechanics that relates the energy of a photon to the frequency of its associated electromagnetic wave. Its value is approximately 6.626 x 10^-34 joule-seconds (J·s). This small value reflects the scale of quantum effects, indicating that the energies associated with quantum states and interactions are typically very tiny, only becoming significant at microscopic scales such as those involving atoms and subatomic particles.

In the context of the choices provided, this value is crucial for understanding phenomena such as the photoelectric effect, where energy is quantized in discrete packets (quanta) proportional to the frequency of light. The other values given correspond to different physical constants or concepts; for example, the speed of light is represented by the first option, while the charge of an electron aligns with another. These constants serve different purposes in physics and do not apply to Planck's constant. Understanding the correct value of Planck's constant is fundamental for solving problems in quantum mechanics and related fields.