"Light is not only a wave; it also possesses the properties of discrete packets of energy (particles)."
This concept, proposed by Albert Einstein, is known as the "light-quantum hypothesis." Light behaves as a collection of particles, each carrying an energy defined by E=hf (where h is Planck's constant and f is the frequency of the light).
When light with sufficient energy strikes the surface of a metal, the electrons within the metal absorb the energy from these light particles in their entirety and are ejected from the surface. This phenomenon is called the "photoelectric effect."
The process of an electron being ejected from the surface of a metal can be likened to a game: "Escaping from an amusement park that uses a 'pay-upon-exit' system."
In this scenario, the kinetic energy K (the change) of a visitor exiting the park is expressed by Einstein’s photoelectric equation:
K=E−W=hf−W
Suppose a visitor inside the park finds a banknote with a value of E1=hf1 (representing a light particle with frequency f1) and uses it to pay the admission fee; the visitor then exits the park with an amount of "change" (kinetic energy) equal to K1.
Next, if the value of the banknote found is increased fourfold to 4E1=h(4f1) (representing a light particle with a frequency four times greater), and a visitor uses this to pay the admission fee, the "change" (kinetic energy) they possess upon exiting becomes K2=13K1 (thirteen times the initial amount).
Determine the ratio of the admission fee (work function W) to the value of the first banknote found (E1=hf1).
The ratio E1W can be expressed as an irreducible fraction qp (where p and q are coprime natural numbers). Provide the value of p×q.
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