Final answer:
The coefficient of kinetic friction (µₖ) between the object and the surface is 5 N/kg (Newton per kilogram).
Step-by-step explanation:
The force of friction (fₖ) can be calculated using the formula fₖ = µₖ ⋅ N, where N is the normal force acting on the object. In this case, the normal force is equal to the weight of the object, which is m ⋅ g (mass multiplied by gravity).
Given that the frictional force is 15 N and the mass is 3 kg, we can set up the equation 15 N = µₖ ⋅ (3 kg ⋅ 9.8 m/s²) to find the coefficient of kinetic friction (µₖ). Solving for µₖ, we get 5 N/kg.
This explanation breaks down the problem, explaining the relevant physics concepts involved in calculating the coefficient of kinetic friction. It includes the formula used, the substitution of known values, and the steps to find the final answer. The use of subscript and superscript style enhances the clarity of the mathematical expressions.