Force and Pressure | SSC CGL Tier 2 - Study Material, Online Tests, Previous Year PDF Download

Introduction

To accomplish tasks, the application of force is necessary. Pressure, on the other hand, refers to the force applied per unit area, emphasizing the force's distribution across a surface. While force represents the overall effect of one object on another, pressure specifically quantifies the force applied to a unit area. The unit of pressure measurement is the pascal, defined as the pressure exerted by one Newtonian force on one square unit area.

Definition of Force and Pressure

Force is the term used to describe a push or pull that causes motion or interacts between two objects. It possesses both magnitude and direction, with changes occurring when these aspects are altered. Pressure, however, is the amount of force acting on a unit area. The distinction lies in force being the total effect, while pressure is a specific quantity of force distributed over a unit.

Similarities and Differences

Similarities exist between force and pressure, with both involving interactions between objects. However, force encompasses the total effect, including magnitude and direction, while pressure specifically addresses force applied to a unit area. The unit of pressure is the pascal, and understanding these concepts is crucial for comprehending physical interactions.

Force and the State of Motion

Force is instrumental in changing the state of motion of an object, influencing speed, direction, or shape. Objects at rest have a net-zero speed, and changes in the state of an object involve applying force. The speed of an object increases when force aligns with motion, and it decreases when applied force opposes motion.

Force and the Shape of an Object

Under the influence of force, objects change shape, exemplified by the alteration in dough shape while making chapati. Without force, objects cannot autonomously change shape, direction, or speed.

1. Contact Forces: Forces acting between objects in direct contact, such as muscular force and friction, are termed contact forces. Muscular force results from muscle action, while friction acts in the opposite direction to object movement.
2. Non-contact Forces: Forces acting on objects without direct contact, including magnetic force, electrostatic force, and gravitational force, are non-contact forces. These forces operate at a distance, like the repulsion or attraction between magnets.

Pressure and Its Calculation

Pressure is the force acting per unit area, expressed as Pressure = Force / Area. A small surface area results in higher pressure. Examples include the pressure exerted by liquids on container walls and gases inside an inflated balloon.

• Atmospheric Pressure: Atmospheric pressure is the force exerted by air on a surface due to gravity. It balances internal body pressure, preventing us from crushing under the force of gravity. The pressure inside our bodies equals atmospheric pressure.

Conclusion

In conclusion, force involves pushes or pulls, causing motion and interacting between objects. It possesses both magnitude and direction, affecting an object's speed, direction, or shape. Pressure, quantified as force per unit area, specifically addresses the distribution of force. Understanding these concepts is essential for grasping the dynamics of physical interactions.