A block rests on a rough incline at to the horizontal ( )

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

Problem

2\,\text{kg}

block rests on a rough incline at

20^{\circ}

to the horizontal (

\tan 20^{\circ}=0.364

). The coefficient of static friction is

0.40

. A student gently pushes the block with a

5\,\text{N}

force directed up the slope, but the block remains at rest. Which one of the following best describes the static friction acting on the block? (Take

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

.) (a) Down the slope, about

1.7\,\text N

(b) Up the slope, about

6.7\,\text N

1.7\,\text N

(d) Up the slope, about

7.4\,\text N