Question

9/11
if the log is being dragged to the right at constant speed, which box is the normal force, ($f_{ground on log, perp}$)?
question 9

Explanation:

The normal force from the ground on an object is a contact force that acts perpendicular to the ground, pushing upward to counteract the downward force of gravity on the object. In the diagram, the upward direction is represented by the box labeled Y.

Answer:

The box labeled Y (the top box along the vertical dashed line) is the normal force $\boldsymbol{F_{ground\ on\ log,\ \perp}}$.