In physics, the unit for k depends on the context in which it is used. One of the most common uses of k is in Hooke’s Law, which relates to springs. In this case, k represents the spring constant, and its unit is typically Newton per meter (N/m).
Another context where k appears is in Coulomb’s Law, where it is the electrostatic constant. Here, its value is approximately 8.99 × 109 N·m2/C2.
Furthermore, k may also represent a rate constant in chemical kinetics, which has units that vary based on the reaction order.
Understanding the specific context is essential to accurately identifying the unit of k in physics.