ICSE Class 10 Physics Important Topics 2025 and Usually Difficult, Confusing Concepts

Force, Work, Power, and Energy

19 to 25 marks

Electricity and Electromagnetism

16 to 24 marks

Light

13 to 29 marks

Mechanics

• Q 2 (iii): Numerical on moments based on non-uniform distribution of mass.
• Q 6 (ii)(b) & (ii)(c): Law of conservation of energy vs. conservation of mechanical energy. Q 6 (i): Definition of centre of gravity. Q 6 (iii): Modification in the diagram of block and tackle system.

Light

• Q4 (i): Sign convention in lenses.
• Q4 (iii): Diagram based Qs from prism.
• Q4 (iii)(b) 1: Calculation of critical angle

Sound

• Q1 (iv): Resonance definition.
• Q7 (i) (b): Numerical on principle of echo.
• Q7 (iii): Relation of length of air column with frequency

Electricity

• Q1 (x): Difference between voltage drop and terminal voltage.
• Q2 (iv): Relationship between resistance, current and brightness of a bulb.

Calorimetry

• Q9 (ii) (a & b): Energy absorption and release during change of phase.
• Q9 (ii) (c): Heat numerical.

Electromagnetism

• Q 9 (iii)(b) 1: Conditions under which different rules such as Right-hand thumb. rule, Fleming’s right-hand and left-hand rule etc.
• Q 9 (iii) (a): Electric motor and AC generator.

Radioactivity

• Q1 (iv): What happens inside nucleus during beta emission.

Mechanics

• Numerical using principle of moment for non-uniform distribution of mass.
• Displacement in calculating work when diagrammatic information is given.
• Purpose of one more pulley in the movable block of block and tackle system.
• Proper definition of the Centre of Gravity and its position in different shapes.
• Difference between principle of conservation of energy and principle of conservation of mechanical energy.
• Modification in the diagram of block and tackle system as per the given diagram.

Light

• Magnification for different cases of lens diagrams.
• Application of combined refraction between lenses and glass block.
• Sign convention in lens formula.
• Diagram based questions from optics.

Sound

• Examples of different vibrations.
• Time to hear echo for humans remain the same in different media but the distance
• changes in different media.
• Frequency is inversely proportional to length

Electricity

• Diagrammatic questions on household wiring.
• Ohm’s law diagram and condition to identify Ohmic conductor.
• Calculation of current in parallel branches.
• Relation between resistance, current drawn and thereby energy consumed.

Calorimetry

• Energy absorption and release during melting and freezing.
• Numerical involving mixtures and change of phase of the substances mixed.

Electromagnetism

• Confusion in factors affecting the Speed of rotation in DC motor and induced
• current in AC generator.
• Confusion in comprehending the diagram when orientation of the diagram is
• changed.

Radioactivity

• Changes inside nucleus during beta emission.
• Completion of balancing radioactive reactions when the reactions are given sequentially and not separate.