A crate is already sliding across a factory floor

PHYSICS · Single correct · AP · Physics 1: Algebra-based · Force and Translational Dynamics · Force and Translational Dynamics

Problem

10\,\text{kg}

crate is already sliding across a factory floor. A worker pushes straight downward on the top of the crate with a force of

30\,\text{N}

while also pushing it horizontally. If the coefficient of kinetic friction between the crate and the floor is

0.35

and

g = 9.8\,\text{m/s}^2

, which value is closest to the magnitude of the kinetic friction force acting on the crate? (a)

34\,\text{N}

(b)

128\,\text{N}

(c)

45\,\text{N}

(d)

64\,\text{N}