To determine if a body is in static equilibrium, we need to consider both its translational and rotational states. Static equilibrium means the body is at rest and remains at rest. This requires that there is no net force causing acceleration and no net torque causing angular acceleration.
C) Both net force and net torque are zero
This option correctly states the two necessary and sufficient conditions for a body to be in static equilibrium. The absence of net force ensures no linear acceleration, and the absence of net torque ensures no angular acceleration. If both are zero, the body remains at rest if it was initially at rest.
For an object, such as a uniform rod, to be in equilibrium, two conditions must be met: translational equilibrium and rotational equilibrium. Translational equilibrium means the object is not accelerating linearly, and rotational equilibrium means it is not accelerating rotationally.
B) The sum of the forces and torques is zero. This option correctly states both conditions required for an object to be in complete equilibrium: zero net force (translational equilibrium) and zero net torque (rotational equilibrium).
The question asks about the definition of stable equilibrium for a body. Equilibrium refers to a state where the net force and net torque on a body are zero. There are three types of equilibrium: stable, unstable, and neutral. We need to identify the characteristic behavior of a body in stable equilibrium when slightly displaced.
Correct Option: A) It returns to its original position after a slight displacement. This statement perfectly describes stable equilibrium. When a body in stable equilibrium is slightly disturbed, a restoring force or torque acts to bring it back to its original, lowest potential energy state.
This question asks about the definition of unstable equilibrium. Understanding the different types of equilibrium (stable, unstable, and neutral) is crucial. Equilibrium refers to a state where the net force and net torque on an object are zero. The stability of this equilibrium depends on how the object behaves when slightly displaced from its equilibrium position.
B) It moves away from its original position after a slight displacement. This accurately describes unstable equilibrium. In this state, any small perturbation causes the object to move further from its equilibrium position, increasing its potential energy.
The question asks for the definition of the center of gravity of a body. We need to evaluate each option based on the fundamental principles of physics related to mass, weight, and rotation.
Correct Option: B) The entire weight can be considered to act
The center of gravity (CG) of a body is defined as the point through which the resultant of the gravitational forces on all the particles of the body acts. In simpler terms, it's the single point where the entire weight of the body can be considered to act, regardless of the body's orientation.
To determine when an object is in equilibrium, we need to consider both its translational and rotational states. Equilibrium implies that the object is either at rest or moving with constant velocity and constant angular velocity. This requires specific conditions related to the forces and torques acting on the object.
Correct Option: C) Both the net force and the net torque acting on it are zero