**Category:** Quantum Physics

**Subtype:** Photoelectric Effect

**Problem Description:** This problem involves calculating the threshold wavelength (or limit) for the photoelectric effect in copper, given the work function (the energy required for an electron to escape from the metal) and using Planck's constant and the speed of light. The goal is to determine the wavelength of light that can just provide enough energy to free an electron from copper. 

**Key Concepts:**
- Work function (\( \phi \)): The minimum energy needed to remove an electron from the surface of a material.
- Threshold wavelength (\( \lambda \)): The maximum wavelength of light that can cause the photoelectric effect, calculated using the relationship between energy and wavelength.

**Formula Used:** 
The energy of a photon is given by the equation:
\[
E = \frac{hc}{\lambda}
\]
where \( E \) is the energy of the photon, \( h \) is Planck's constant, \( c \) is the speed of light, and \( \lambda \) is the wavelength. 

To find the threshold wavelength, rearrange the formula:
\[
\lambda = \frac{hc}{E}
\]

In this case, \( E \) is the work function of copper, \( 6.625 \times 10^{-19} \, \text{J} \). 

**Objective:** Calculate the threshold wavelength for copper and select the correct answer from the provided options.