force polygon closes

funicular polygon closes

both force polygon and funicular polygon close

all the forces are concurrent

any copianar force system

a system of parallel forces only

concurrent copianar force system

non-concurrent copianar force system

triangle

open polygon

closed polygon

parallelogram

vector diagram

space diagram

force diagram

funicular diagram

(i) and (ii)

(i) and (iii)

only (i)

(i), (ii) and (iii)