Complete RGPV exam-oriented page covering centroid, centre of gravity, moment of inertia, radius of gyration, product of inertia, support reactions, shear force, bending moment, SFD, BMD, cantilever beam and simply supported beam.
Centre of Gravity & Moment of Inertia important topics
Easy revision notes for RGPV exam
Centroid is the geometrical center of a plane figure. It depends only on the shape of the body and is independent of material density.
Centre of gravity is the point through which the total weight of a body acts. It is used in stability analysis, vehicle design and building structures.
Moment of inertia is the property of a body that resists rotational motion. Area moment of inertia is used in bending analysis of beams.
Radius of gyration is the distance from an axis at which the whole area or mass can be assumed to be concentrated.
Product of inertia measures distribution of area with respect to two perpendicular axes. It is useful for unsymmetrical sections and structural analysis.
Support reactions are forces developed at supports of beams and structures. They are calculated using equilibrium equations.
Shear force is the algebraic sum of vertical forces acting on either side of a section. SFD shows variation of shear force along beam length.
Bending moment is the turning effect produced by external forces on a beam section. BMD shows variation of bending moment along the beam.
Cantilever beam is fixed at one end and free at the other end. Examples include balconies, bridges and aircraft wings.
Simply supported beam is supported at both ends. It is commonly used in building structures and bridges.
Most important formulas
High chance RGPV exam questions
Repeated questions from RGPV previous year papers
| Topic | Repeated Questions | Frequency | Priority |
|---|---|---|---|
| SFD & BMD | Cantilever beam, simply supported beam, point load, UDL and numerical problems | Very High | ★★★★★ |
| Support Reactions | Beam reaction problems and equilibrium equations | Very High | ★★★★★ |
| Moment of Inertia | Derivation for rectangle and circle, numerical problems | Very High | ★★★★★ |
| Centroid & C.G. | Definitions, differences and centroid of composite sections | High | ★★★★ |
| Beam Numerical Problems | SFD, BMD, support reactions and loading diagrams | High | ★★★★ |
| Radius of Gyration | Formula, applications and numerical problems | Medium | ★★★ |
| Cantilever & Simply Supported Beam | Differences, behavior and loading diagrams | Medium | ★★★ |
| Product of Inertia | Product of inertia and principal axes | Medium | ★★★ |
Use this section to improve answer quality in RGPV exams
For 14-mark answers: Start with definition, write formulas, draw a neat diagram, explain steps and end with applications. For SFD and BMD problems, first calculate support reactions, then make shear force table and bending moment table before drawing final diagrams.
For numericals: Always mention sign convention, units and final answer clearly. In moment of inertia questions, write the standard formula first and then apply parallel axis theorem or perpendicular axis theorem where required.
High scoring topics: Moment of inertia derivations, centroid of composite sections, support reaction problems, cantilever beam diagrams, simply supported beam diagrams, SFD and BMD are repeatedly asked topics.
Keep these PDFs in the same folder as this HTML file
Common student doubts
SFD & BMD, support reactions, moment of inertia, centroid and centre of gravity are the most important topics.
Support reactions, moment of inertia, centroid, SFD, BMD and radius of gyration numericals are important.
SFD, BMD, cantilever beam, simply supported beam, loading diagrams and centroid diagrams are important.