Answer :
Explanation:
i) Equilibrium
Equilibrium refers to a state of balance between opposing forces or influences. In this state, the net force acting on an object is zero, resulting in either:
Static equilibrium: The object remains at rest (no motion). Imagine a book placed flat on a table. The force of gravity pulling the book down is balanced by the upward force exerted by the table.
Dynamic equilibrium: The object is in motion, but its velocity (speed and direction) remains constant. A bike moving at a steady speed on flat ground experiences opposing forces (friction and air resistance) that are balanced by the forward force applied by the rider.
Equilibrium is a fundamental concept in various fields, including:
Physics: It's crucial for understanding mechanics, statics, and dynamics.
Chemistry: Chemical reactions reach equilibrium when the rates of the forward and reverse reactions become equal.
Economics: Supply and demand reach equilibrium when the quantity of a good or service produced equals the quantity demanded.
ii) Resultant Force
The resultant force is the single force that has the same effect as all the individual forces acting on an object combined. It's calculated by adding the vectors (considering both magnitude and direction) of all the forces.Imagine you're pushing a box with two hands: one hand applies a force to the right, and the other applies a force slightly upwards and to the right. The resultant force would be the single force that would move the box in a specific direction with a particular speed, considering the combined effect of both your pushes.
The resultant force determines the object's acceleration (change in velocity). If the resultant force is zero (equilibrium), the object remains at rest or continues moving with constant velocity. If the resultant force is not zero, the object will accelerate in the direction of the resultant force.
iii) Center of Gravity (CG)
The center of gravity (CG) is the point where the entire weight of an object is considered to be concentrated. It's the point at which the force of gravity acts. The location of the CG depends on the object's shape and mass distribution.
Imagine a seesaw with two children sitting on opposite ends. The CG of each child and the seesaw itself play a role in determining where the seesaw will balance. The seesaw will balance when the total torque (turning effect) caused by the weight of each child relative to the fulcrum (pivot point) is equal on both sides. The CG is often located near the object's geometric center, but it can be higher or lower depending on the mass distribution.
The CG is crucial for understanding an object's stability. A low CG makes an object more stable, as it's harder to tip it over. A high CG makes an object less stable, as it's easier to topple. For instance, a wide-base pyramid has a low CG and is very stable, while a tall, thin tower has a high CG and can be more easily knocked over