An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (1)
The equation used by Albert Einstein to explain the photoelectric effect relates energy (E), Planck's constant (h), and frequency (v). The correct equation is:
Recall the relationship: E = h u
Identify the correct option: E = h v
The equation is: E = h v .
Explanation
Understanding the Problem The problem asks us to identify the equation used by Albert Einstein to describe the photoelectric effect, given the variables E for energy, h for Planck's constant, and v for frequency.
Recalling the Photoelectric Effect Equation The equation that correctly relates energy, Planck's constant, and frequency in the context of the photoelectric effect is: E = h × v This equation states that the energy of a photon (E) is equal to Planck's constant (h) multiplied by the frequency of the light (v).
Comparing with Given Options Comparing the recalled equation with the given options:
E = v h (Incorrect: Energy is inversely proportional to frequency)
E = h v (Correct: Energy is directly proportional to frequency)
E = h u (Incorrect: Energy is inversely proportional to Planck's constant)
E = h − v (Incorrect: Energy is the difference between Planck's constant and frequency)
Identifying the Correct Equation Therefore, the correct equation is: E = h v
Examples
The photoelectric effect, explained by Einstein's equation E = h v , is the foundation for solar panels. When light (photons) strike a material, they transfer energy ( E ) to electrons. If the energy is high enough (determined by the light's frequency v and Planck's constant h ), electrons are emitted, creating an electric current. Solar panels use this principle to convert sunlight into electricity, providing a clean and renewable energy source. The efficiency of this conversion depends directly on understanding and applying Einstein's equation.
