Physics
Answer
According to the principle of moments, if the algebraic sum of moments of all the forces, acting on the body, about the axis of rotation is zero, the body is in equilibrium. Therefore, as per the principle of moments,
sum of anticlockwise moments = sum of clockwise moments
For example, a physical balance works on the principle of moments.
Related Questions
State the condition when a body is in
(i) static equilibrium.
(ii) dynamic equilibrium.
Give one example each of static and dynamic equilibrium.
State two conditions for a body, acted upon by several forces to be in equilibrium.
A, B and C are the three forces each of magnitude 4N acting in the plane of paper as shown in figure. The point O lies in the same plane.
(i) Which force has the least moment about O? Give reason.
(ii) Which force has the greatest moment about O? Give reason.
(iii) Name the forces producing (a) clockwise, (b) anticlockwise moments.
(iv) What is the resultant torque about the point O?
A body is acted upon by two forces each of magnitude F, but in opposite directions. State the effect of the forces if
(a) both forces act at the same point of the body.
(b) the two forces act at two different points of the body at a separation r.