Question

a 7 kg object accelerates at +0.5 m/s² across a sidewalk. which of the following formulas should be used to calculate the amount of friction the object will experience?
○ f_fk = (μ_fk)(f_n)
○ f_g = mg
○ f_net = ma

Explanation:

Step1: Analyze the problem

The problem is about calculating the friction force on an object. The formula for kinetic friction is \(F_{FK}=(\mu_{FK})(F_{N})\), where \(\mu_{FK}\) is the coefficient of kinetic friction and \(F_{N}\) is the normal force.

Step2: Evaluate each option

• \(F_{NET} = ma\) is Newton's second law for net force, not for friction.
• \(F_{g}=mg\) is the formula for gravitational force, not friction.
• \(F_{FK}=(\mu_{FK})(F_{N})\) is the correct formula for kinetic friction.

Answer:

\(F_{FK}=(\mu_{FK})(F_{N})\)