Equilibrium of a Rigid Body: Moments of Forces and Center of Gravity

What is the term used to describe a moment of force that tends to rotate a body in an anticlockwise direction?

Which classification of moment of force describes a moment that tends to rotate a body about a fulcrum?

What type of moment tends to bend a body about one of its fixed ends?

In which direction does a twisting moment act on a shaft?

What is the center of gravity in physics?

Which concept is fundamental to understanding the intact stability of a floating body?

What is the mathematical definition of moment of force?

Which formula represents the moment of force?

In what unit is the moment of force measured in the SI system?

What type of moment is produced when a force rotates a body in a clockwise direction?

What is the center of gravity of a body?

Which term refers to the division of moments based on their direction of rotation?

What is the formula for calculating torque?

Which type of force acts perpendicular to the surface of contact between two objects?

What does the Frictional Force oppose?

Which force can be either static or kinetic?

What is the primary force responsible for causing motion, deformation, or internal stresses in a rigid body?

In the formula τ = rFsinθ, what does θ represent?

Equilibrium of a Rigid Body

Moment of force: the rotational tendency of a force, defined as the product of force and perpendicular distance from the point to the line of action of the force (M = F × d)
Unit of moment of force: newton meter (N-m) in SI, newton centimeter (N-cm) in CGS

Types of Moment of Force

Clockwise moment: when a force acting on a body has the tendency to rotate the body in a clockwise direction
Anticlockwise moment: when a force acting on a body has the tendency to rotate the body in an anticlockwise direction

Classification of Moment of Force

Turning moment: tends to rotate a body about a fulcrum
Bending moment: tends to bend a body about one of its fixed ends
Twisting moment: twists a shaft about one of its fixed ends

Center of Gravity

Imaginary point in a body of matter where the total weight of the body may be thought to be concentrated
Concept useful in designing static structures or predicting the behavior of a moving body acted on by gravity

Torque

Magnitude given by the equation: τ = rFsinθ
Where τ is the torque, r is the distance from the pivot point to the point where the force is applied, F is the magnitude of the force, and θ is the angle between the force and the vector directed from the point of application to the pivot point

Contact Forces on a Rigid Body

Normal force (N): acts perpendicular to the surface of contact between the two objects, prevents interpenetration, and has a magnitude typically equal to the force pressing the objects together
Frictional force (F): arises due to microscopic irregularities on the surfaces of the objects in contact, opposes relative motion, and has a magnitude dependent on the normal force and coefficient of friction
Applied force (F): any external force exerted directly on the rigid body by another object, can have any direction and magnitude, and is responsible for causing motion, deformation, or internal stresses in the rigid body

This quiz covers the principles of moment of forces, the concept of the center of gravity of a body, types of contact forces on a rigid body, and calculations related to forces acting on a rigid body. Learn about rotational tendencies of forces and how they affect the equilibrium of rigid bodies.