According to Lami’s theorem___________________?

According to Lami’s theorem___________________?

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 particle 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 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

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 surfaces
E. will be in equilibrium under all conditions