Pressure in the container before it was opened

An airtight container having a lid with negligible mass and an area of 77 cm2 is partially evacuated. If a 480 N force is required to pull the lid off the container and the atmospheric pressure is 1.0 ×105 N/m2, what was the air pressure in the container before it was opened. Fluid mechanics is a fundamental topic in physics and engineering that explains the behavior of liquids and gases at rest and in motion. The lesson is structured to build understanding from basic definitions to key governing principles used in real-world problem solving. We begin by defining fluids and distinguishing between fluid statics and fluid dynamics. The video then explains important physical properties such as density, pressure, and viscosity, followed by how pressure varies with depth in a fluid. Core principles, including the continuity equation and Bernoulli’s equation, are carefully explained, with emphasis on their physical meaning and applications. The lesson also introduces different types of flow, including laminar and turbulent flow, and discusses how these concepts apply in practical situations such as pipe systems, atmospheric motion, and engineering design. Clear explanations and step-by-step reasoning make this video suitable for both beginners and students preparing for examinations. Topics covered in this video: • Definition and properties of fluids • Density, pressure, and hydrostatic variation • Fluid statics and fluid dynamics • Continuity equation (conservation of mass) • Bernoulli’s equation and energy conservation • Viscosity and resistance to flow • Laminar and turbulent flow • Real-life applications of fluid mechanics This video is ideal for GCE students, high school learners, and introductory engineering courses. It is designed to strengthen conceptual understanding and support problem-solving skills in examinations. #FLUIDMECHANICS #FLUIDMECHANICSFULLCOURSE #FLUIDMECHANICSEXPLAINED #FLUIDMECHANICSFORBEGINNERS #PHYSICSFLUIDMECHANICS #FLUIDDYNAMICS #FLUIDSTATICS #BERNOULLIEQUATION #CONTINUITYEQUATION #VISCOSITYPHYSICS #LAMINARVSTURBULENT #PRESSUREINFLUIDS #DENSITYPHYSICS #HYDROSTATICPRESSURE #GCEPHYSICS #HIGHSCHOOLPHYSICS #ENGINEERINGFLUIDMECHANICS #EXAMREVISION #PHYSICSTUTORIAL #LEARNPHYSICSFAST #PHYSICSPROBLEMSOLVING #MECHANICSOFEFLUIDS #SCIENCEEDUCATION