Is the F Pointing to the Right Friction or Force of the Truck Accelerating?

[xzibition8612]

Homework Statement

See attachment.

Homework Equations

The Attempt at a Solution

My only question concerns the free body diagram. In the attachment, is the F pointing to the right friction or force of the truck accelerating? Why is the line of action of N not go through the mass center? And shouldn't friction for the cabinet point toward the left since a force is pulling it right?
I'm very confused about this.
Any help is appreciated thanks.

 

[tiny-tim]

hi xzibition8612!

In the attachment, is the F pointing to the right friction or force of the truck accelerating?

both …

the only horizontal force on the cabinet is the friction force ​

And shouldn't friction for the cabinet point toward the left since a force is pulling it right?

see above

Why is the line of action of N not go through the mass center?

take moments about the point below the centre of mass …

the centre of mass is accelerating, so there's a non-zero moment of acceleration about that point, which show that the normal force must also have a non-zero moment