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Explain motion, forces, light, sound and electricity.
8 GUIDES · ENGLISH & HINDI
Start with a level that fits what you already know. Each guide includes explanations, practice and answers. About learning levels →
Physics
BeginnerA measured bench length and a calculator result are not equally certain.
Learning outcome: Read instruments thoughtfully, convert units, distinguish random variation from a systematic offset, and report a calculated quantity without overstating its precision.
Read the guide →Physics
BeginnerA steel tumbler and a cloth bag in the same room can feel different even when their temperatures are equal.
Learning outcome: Explain conduction, convection and radiation, calculate simple heating and mixing cases, and state which energy transfers a model ignores.
Read the guide →Physics
BeginnerWhen a school announcement reaches the back of a room, air from the loudspeaker has not travelled all the way into every listener’s ear.
Learning outcome: Distinguish particle motion from wave motion, calculate wavelength and echo distance, and explain the main stages of hearing using a labelled paper model.
Read the guide →Physics
BeginnerA printed page, a mirror image and a pencil seen through water all become visible because light reaches the eye.
Learning outcome: Construct plane-mirror ray diagrams, distinguish real and virtual images, predict basic refraction directions and calculate refractive index from speed.
Read the guide →Physics
IntermediateA student can walk a long route and finish near the starting point.
Learning outcome: Calculate journey averages, interpret position–time and velocity–time graphs, and solve constant-acceleration problems while checking when their assumptions apply.
Read the guide →Physics
IntermediateA trolley can move with balanced forces or stay still while someone pushes it.
Learning outcome: Use force diagrams, distinguish action–reaction pairs from balanced forces, and calculate acceleration and average stopping force under stated assumptions.
Read the guide →Physics
IntermediateLifting the same box slowly or quickly changes the required average power, while the ideal energy transfer can stay the same.
Learning outcome: Calculate signed work, kinetic and gravitational potential energy, distinguish energy from power, and test whether a mechanical-energy shortcut is justified.
Read the guide →Physics
IntermediateA torch needs a complete conducting path, a source of energy and components that transfer that energy.
Learning outcome: Explain circuit quantities, analyse ideal series and parallel resistor networks, and check charge and energy accounts entirely with paper diagrams.
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