Equilibrium of Forces

Contents & notes: what this topic covers

Under Equilibrium of Forces, the JAMB Physics syllabus expects you to study:

• 5. Equilibrium of Forces
• (a) equilibrium of particles:
• (i) equilibrium of coplanar forces;
• (ii) triangles and polygon of forces;
• (iii) Lami’s theorem.
• (b) principles of moments
• (i) moment of a force;
• (ii) simple treatment and moment of a couple
• (torque);
• (iii) applications.
• (c) conditions for equilibrium of rigid bodies under the action of parallel and non- vii. a parallel forces
• (i) resolution and composition of forces in pr two perpendicular directions;
• (ii) resultant and equilibrant.
• (d) centre of gravity and stability o
• (i) stable, unstable and neutral equilibra.
• x (6) Friction
• (i) static and dynamic friction; C
• (ii) coefficient of limiting friction and its
• (iii) advantages and disadvantages of friction
• (iv) reduction of friction;
• (v) qualitative treatment of viscosity and terminal velocity;
• (vi) Stoke’s law.
• i v (7) (a) Work, Energy and Power v
• (i) definition of work, energy and power;
• (ii) forms of energy; C
• (iii) conservation of energy;
• (iv) qualitative treatment between different forms of energy;
• (v) interpretation of area under the force- distance curve.
• (b) Energy and society v
• (i) sources of energy; v
• (ii) renewable and non-renewable energy e.g., coal, crude oil sun, wind etc.;
• (iii) uses of energy;
• (iv) energy and development;
• (v) energy diversification;
• (vi) environmental impact of energy e.g., x global warming, greenhouse effect and spillage;
• (vii) energy crises;
• (viii) conversion of energy;
• (ix) devices used in energy production.
• (c) Dams and energy production
• (i) location of dams
• (ii) energy production
• (d) nuclear energy
• (e) solar energy
• (i) photoelectric effect
• (ii) solar collector;
• (iii) solar panel for energy supply.

Study notes & guidance

Study Equilibrium of Forces using a recommended Physics textbook that follows the JAMB syllabus. Work through the contents listed above one by one, make brief notes in your own words, and then practise as many questions on this topic as you can — in Physics, understanding and steady practice matter far more than memorising. Use the objectives below as a checklist: if you can do each one confidently, you have mastered this topic.

Objectives — candidates should be able to

After studying Equilibrium of Forces, you should be able to:

1. Apply the conditions for the equilibrium of coplanar forces to solve problems;
2. Use triangle and polygon laws of forces to solve equilibrium problems;
3. Use Lami’s theorem to solve problems; analyse the principle of moment of a force;
4. Determine moment of a force and ouple;
5. Describe some applications of moment of a force and couple; pply the conditions for the equilibrium of rigid bodies to solve oblems;
6. Resolve forces into two perpendicular directions;
7. Determine the resultant and equilibrant f forces;
8. Differentiate between stable, unstable and neutral equilibra. andidates should be able to:
9. Differentiate between static and dynamic friction;
10. Determine the coefficient of limiting friction;
11. Compare the advantages and disadvantages of friction;
12. Suggest ways by which friction can be reduced;
13. Analyse factors that affect viscosity and terminal velocity;
14. Apply Stoke’s law. andidates should be able to:
15. Differentiate between work, energy and power;
16. Compare different forms of energy, giving examples;
17. Apply the principle of conservation of energy;
18. Examine the transformation between different forms of energy;
19. Interpret the area under the force – distance curve.
20. Solve numerical problems in work, energy and power.
21. Itemize the sources of energy;
22. Distinguish between renewable and non- renewable energy, examples should be given;
23. Identify methods of energy transition;
24. Explain the importance of energy in the development of the society;
25. Analyze the effect of energy use to the environment;
26. Identify the impact of energy on the environment;
27. Identify energy sources that are friendly or hazardous to the environment;
28. Identify energy uses in their immediate environment;
29. Suggests ways of safe energy use
30. State different forms of energy conversion.
31. Photovoltaic cells
32. Work function (  = hf)
33. Xix. Planck’s constant

These objectives are from the official JAMB syllabus. Use them as a checklist — if you can do each one confidently, you have mastered this topic.

Source: official JAMB UTME Physics syllabus (IBASS, jamb.gov.ng). Reproduced for study use. Last checked: 17 Sept 2026. Always confirm the current syllabus on the official portal.