The magnitude of two forces, which when acting at right angle produce resultant force of VlOkg and when acting at 60° produce resultant of Vl3 kg. These forces are____________________?

The magnitude of two forces, which when acting at right angle produce resultant force of VlOkg and when acting at 60° produce resultant of Vl3 kg. These forces are____________________?

A. 2 and V6
B. 3 and 1 kg
C. V5andV5
D. 2 and 5
E. none of the above

According to law of triangle of forces______________?

According to law of triangle of forces______________?

A. three forces acting at a point will be in equilibrium
B. three forces acting at a point can be represented by a triangle, each side being proportional to force
C. if three forces acting upon a patticle are represented in magnitude and direction by the sides of a triangle, taken in order, they will be in equilibrium
D. if three forces acting at a point are in equilibrium, each force is proportional to the sine of the angle between the other two
E. none of the above

According to principle of moments_________________?

According to principle of moments_________________?

A. if a system of coplanar forces is in equilibrium, then their algebraic sum is zero
B. if a system of coplanar forces is in equilibrium, then the algebraic sum of their moments about any point in their plane is zero
C. the algebraic sum of the moments of any two forces about any point is equal to moment of theiwesultant about the same point
D. positive and negative couples can be balanced
E. none of the above

A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if______________?

A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if______________?

A. the floor is smooth, the wall is rough
B. the floor is rough, the wall is smooth
C. the floor and wall both are smooth surfaces
D. the floor and wall both are rough sur-faces
E. will be in equilibrium under all condi-tions