NEB Physics Practicals — Class 12

The Class 12 NEB practical exam is all about waves, circuits and light: resonance tubes, sonometers, meter bridges, potentiometers, galvanometers, optical benches and prisms. This course gives you a working virtual version of each apparatus. You hunt for resonance by ear, chase galvanometer nulls with a jockey, remove parallax on an optical bench and sweep a ray through minimum deviation — recording data tables and computing results exactly as the board examiner expects.

You will learn: doneLocating resonance and null points precisely doneWiring and reading electrical meters doneTabulating V-I, balance-length and u-v data doneGraphical analysis: slopes, intercepts and minima doneError analysis and standard precautions

play_arrow Start course play_lesson8 lessons schedule~127 min total

Lessons

1 graphic_eq Resonance Tube: Speed of Sound Strike a tuning fork, slide the water level down the tube and catch the two loudness peaks — then v = 2f(l₂ − l₁) gives the speed of sound in the room. 3D virtual lab 16 min done 2 music_note Sonometer: Laws of Vibrating Strings Slide the bridge and pile on weights until the paper rider leaps off the wire — resonance! — then verify that f×L stays constant for each fork. 3D virtual lab 16 min done 3 electric_bolt Ohm's Law & Resistivity Slide the rheostat, log ammeter-voltmeter pairs into a table, draw the V-I line and turn its slope into the resistivity of the wire on your bench. 3D virtual lab 16 min done 4 balance Meter Bridge: Unknown Resistance Tap the jockey along a one-metre wire until the galvanometer sits dead on zero, then let X = R(100 − l)/l expose the unknown resistor. 3D virtual lab 15 min done 5 settings_input_component Potentiometer: Comparing EMFs Balance two cells one after another on a four-metre wire and let E₁/E₂ = l₁/l₂ compare their EMFs — without drawing a single microamp from either. 3D virtual lab 16 min done 6 speed Galvanometer: Figure of Merit Feed a galvanometer tiny known currents through a high-resistance box, read the deflection in divisions, and compute k = I/θ — the current behind each division. 3D virtual lab 14 min done 7 center_focus_strong Focal Length of Mirrors & Lenses Slide pins along an optical bench, kill the parallax between pin and image, log u-v pairs and let both the formula and the 1/v-1/u graph reveal f. 3D virtual lab 17 min done 8 change_history Prism: Angle of Minimum Deviation Sweep the incident ray across a 60° prism, watch the deviation dip through a minimum, and convert Dₘ into the refractive index of the glass. 3D virtual lab 17 min done