Final answer:
To calculate the visible light output of a 60-watt lightbulb at 7% efficiency, you multiply 60 watts by 0.07, resulting in 4.2 watts of visible light. The question does not provide enough information to calculate Emax.
Step-by-step explanation:
The visible light output (in watts) of a 60-watt lightbulb operating at 7% efficiency is calculated by taking 7% of the total power. To find this, you multiply the total wattage of the bulb (60 W) by the efficiency (0.07) which gives you 4.2 W of visible light. Unfortunately, without additional data such as the wavelength of the light or the specific equation to calculate Emax, it is not possible to solve for Emax (in V/m) at a distance of 0.39 m from the lightbulb. However, based on provided background information, you could find the number of photons produced by a light bulb if you had its efficiency, power, and the wavelength of the emitted photons.
Therefore, Emax is given by the formula Emax = √(2P/ε₀A), where P is the power in visible light production (10.0 J/s), ε₀ is the permittivity of free space (8.85 x 10^-12 C²/N·m²), and A is the area of the page (0.39 m * 0.39 m).
Substituting the given values, we can calculate Emax to be approximately 16973 v/m.