Find your next explanation
Search chapter titles, developed concepts and problem summaries. Try a physical idea such as “friction”, “SHM” or “diffraction”.
661 results
Clear filtersConcept section
Spring-mass oscillators →
Teaching section in Oscillations: restoring forces, phase and energy. Build spring and pendulum models from equilibrium, then connect their motion to energy and initial conditions.
Concept section
Static equilibrium →
Teaching section in Torque, rotational inertia and fixed-axis dynamics. Derive the axis-dependent quantities that connect turning forces to angular motion.
Concept section
Stefan–Boltzmann law →
Teaching section in Thermal radiation and the wavelength of a spectral peak. Separate emission from net exchange, count the relevant areas and connect temperature to a broad spectrum.
Concept section
Temperature dependence of resistance →
Teaching section in Current, resistance and circuit constraints. Connect microscopic drift to wire geometry, circuit topology and temperature-dependent power.
Concept section
Temperature scales →
Teaching section in Units: keep the quantity, change the number. Use units as part of the calculation, including powers, rates and experimental scales.
Concept section
Thermal equilibrium →
Teaching section in Heat balances, conduction and cooling. Track energy through mixing and phase changes, then distinguish steady heat flow from a changing temperature.
Concept section
Torque →
Teaching section in Torque, rotational inertia and fixed-axis dynamics. Derive the axis-dependent quantities that connect turning forces to angular motion.
Concept section
Total internal reflection →
Teaching section in Refraction, internal reflection and dispersion. Draw the normal, trace each boundary and let the geometry decide which formula applies.
Concept section
Transformers →
Teaching section in Coupled coils and transformer reasoning. Track shared flux, winding polarity, stored energy and the load seen by the source.
Concept section
Two-dimensional collisions →
Teaching section in Impulse, momentum and collisions. Choose the system and interval, then connect momentum exchange to centre-of-mass motion and impact outcomes.
Concept section
Uniformly accelerated reference frames →
Teaching section in Connected bodies, sliding friction and accelerating frames. Build force equations from the system, the contact state and the geometry of each connection.
Concept section
Velocity selector →
Teaching section in Magnetic forces, selected velocities and current-produced fields. Use cross products for direction, circular dynamics for motion and Biot–Savart geometry for field sources.
Concept section
Wave phase →
Teaching section in Interference: phase, brightness and contrast. Predict what a detector reads by connecting path, phase and field addition.
Concept section
Wave power and intensity →
Teaching section in Travelling waves, superposition and energy. Read a wave equation, distinguish particle motion from propagation and connect phase to energy transport.
Concept section
Wave superposition →
Teaching section in Travelling waves, superposition and energy. Read a wave equation, distinguish particle motion from propagation and connect phase to energy transport.
Concept section
Wien’s displacement law →
Teaching section in Thermal radiation and the wavelength of a spectral peak. Separate emission from net exchange, count the relevant areas and connect temperature to a broad spectrum.
Concept section
Young modulus experiment →
Teaching section in Elastic response and measuring Young’s modulus. Separate material stiffness from specimen geometry, then infer a modulus from a controlled extension experiment.
Concept section
Zener voltage regulation →
Teaching section in Semiconductor junctions, rectifiers and Zener regulation. Explain the carriers, choose a diode model and verify the operating state before trusting the output.
Practice problem
A band gap sets an absorption energy threshold →
Intermediate · Apply a principle. What is the longest vacuum wavelength whose photon energy can bridge this gap?
Practice problem
A biconvex lens in a liquid →
Intermediate · Connect concepts. Find its focal length in the liquid.