A block is released from rest on a rough plane that is inclined at above the horizontal

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A block is released from rest on a rough plane that is inclined at

30^{\circ}

above the horizontal. Which choice of coordinate axes will most simplify writing Newton’s second-law equations for the block’s motion? (a)

x

-axis horizontal and

y

-axis vertical (b)

x

-axis parallel to the plane (down the slope) and

y

-axis perpendicular to the plane (c)

x

-axis perpendicular to the plane (upward) and

y

-axis parallel to the plane (up the slope) (d)

x

-axis parallel to the plane (up the slope) and

y

-axis perpendicular to the plane