Question

According to lami's theorem

a. The three forces must be equal

b. The three forces must be at 120? To each other

c. The three forces must be in equilibrium

d. If the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two

Answer 1

Option D is correct: According to Lami's theorem, if the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two.

• Lami's theorem doesn't require the three forces to be equal, hence option A will be incorrect.
• It is not important for the forces to make an angle of 120° to obey Lami's rule. Hence option B is also incorrect.
• Option C only says that the forces must be in equilibrium, which is incomplete, hence it is not the correct option.

Thus, Option D is the correct option.