An object slides on a level floor. It slows and comes to a stop with a constant acceleration of magnitude 2.4 m/s². What is the coefficient of kinetic friction between the object and the floor?
A) 0.12
B) 0.24
C) 0.48
D) It is impossible to determine without knowing the mass of the object.

Question

Quizplus · Accepted Answer

The coefficient of kinetic friction ($\mu_k$) can be found using the formula $\mu_k = \frac{a}{g}$, where $a$ is the acceleration (2.4 m/s²) and $g$ is the acceleration due to gravity (approximately 9.8 m/s²). Thus, $\mu_k = \frac{2.4}{9.8} \approx 0.24$. The mass of the object is not needed because it cancels out in the equation for frictional force ($f = \mu_k \cdot m \cdot g$), making the coefficient of kinetic friction independent of mass.

An Object Slides on a Level Floor