Applied Mechanics and Graphic Statics
If a set of given forces are such that their free vectors build a closed polygon, then

The resultant force is zero but resultant couple may not be zero
The resultant force and resultant couple both may not be zero
The resultant force is zero but resultant couple is not zero
The resultant force and resultant couple are always zero

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
One end of an elastic string of natural length ‘l’ and modulus ‘X’ is kept fixed while to the other end is attached a particle of mass m which is hanging freely under gravity. The particle is pulled down vertically through a distance ‘x’, held at rest and then released.The motion is

A damped oscillatory motion
A rectilinear motion with constant speed
None of these
A simple harmonic motion

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
The force acting on a point on the surface of a rigid body may be considered to act

On any point on the line of action of the force
At any point on the surface normal to the line of action of the force
On the periphery of the body
At the centre of gravity of the body

ANSWER DOWNLOAD EXAMIANS APP