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Gravity is a fundamental force that acts on all objects with mass. It is the attractive force between two masses. On Earth, this force gives weight to physical objects and causes them to fall towards the ground when dropped. The force of gravity acting on an object is calculated using the formula:

• \( \mathbf{F} = m \mathbf{g} \)

Here, the force \( \mathbf{F} \) is measured in newtons (N), which quantifies the gravitational pull on an object. The variable \( m \) represents mass in kilograms, and \( \mathbf{g} \) is the acceleration due to gravity, which is typically \( 9.8 \text{ N/kg} \) on Earth. For our exercise, a 2-kg disco ball experiences a gravitational force calculated as \( 19.6 \text{ N} \). This result demonstrates how the mass and gravitational constant interact to determine the gravitational force.

Mass is a measure of the amount of matter in an object and is typically measured in kilograms (kg). It is a scalar quantity, meaning it has magnitude but no direction. Unlike weight, which is the force exerted by gravity on an object, mass is constant regardless of location.

• Mass represents how much of an object you have.
• It influences the gravitational force acting on the object; more mass means more gravitational force.

In our given problem, the disco ball has a mass of 2 kg. This mass is pivotal in determining the gravitational force using the formula \( \mathbf{F} = m \mathbf{g} \). The consistent mass of the disco ball contributes directly to the force experienced due to gravity.

Tension is the force exerted through a string, rope, cable, or chain when it is pulled tight by forces acting from opposite ends. In our exercise, the chain holding the disco ball experiences tension. Tension works to counteract the gravitational force pulling the disco ball downward.When an object is in static equilibrium, the tension in the chain must equal the gravitational force to prevent the object from moving. This means that the magnitude of the tension force \( \mathbf{T} \) in the disco ball's chain is equal to \( 19.6 \text{ N} \), the same as the gravitational force. Understanding tension helps in analyzing forces in systems where objects are held in place by strings or cables.

Static equilibrium refers to a state where an object is at rest and all forces acting upon it are balanced. For an object to be in static equilibrium:

• All forces must add up to zero, resulting in no net force.
• The object must be stationary or moving with constant velocity.

In the context of our problem, the disco ball hanging from the ceiling is in static equilibrium. The upward tension in the chain perfectly counters the downward gravitational force, resulting in no movement. Studying static equilibrium involves ensuring that each force contributes to maintaining balance, which is crucial for understanding and solving real-world engineering and physics problems involving stationary systems.