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

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
The phenomenon of collision of two elastic bodies takes place because bodies

Immediately after collision come momentarily to rest
Attempt to regain its original shape due to their elasticities
Tend to compress each other till they are compressed maximum possible
All listed here

ANSWER DOWNLOAD EXAMIANS APP

Applied Mechanics and Graphic Statics
Newton's law of Collision of elastic bodies states that when two moving bodies collide each other, their velocity of separation

Bears a constant ratio to their velocity of approach
Is inversely proportional to their velocity of approach
Is directly proportional to their velocity of approach
Is equal to the sum of their velocities of approach

ANSWER DOWNLOAD EXAMIANS APP