Physics · Practical apparatus
65 free physics experiments and lesson notes for Practical apparatus, with model limits, worked examples and Tamil explanations.
A vernier compares two scales with slightly different divisions. Ten vernier divisions span nine millimetres, so adjacent divisions differ by 0.1 mm. The coinciding line identifies the fractional part of a millimetre. A positive zero error makes the indicated value too large; subtract it.
Run this experiment →A screw advances by its pitch in one full turn. Dividing that turn into many thimble marks gives a small least count. Include visible half-millimetre marks on the sleeve before adding the thimble reading. Correct a known zero error with its sign.
Run this experiment →Use a graduated cylinder to measure a fully submerged irregular solid or lamina. The difference removes a common additive zero error; two rounded readings still contribute resolution uncertainty.
Run this experiment →The three legs define an equilateral triangle and the central screw measures sagitta h. Correct the flat-plate zero before finding a spherical surface radius.
Run this experiment →Add known weights until the corrected pointer reaches zero. Equal arms compare masses directly; unequal arms need a lever-ratio correction.
Run this experiment →Two measured string tensions add as vectors. A third string placed opposite the resultant balances the knot when its tension matches the resultant magnitude.
Run this experiment →Time many cycles to reduce the effect of stopwatch resolution. Adjust bob mass to confirm the ideal period is independent of mass; use the length to the centre of the bob.
Run this experiment →Tilt a surface until gravity exceeds the stated drag threshold. The rolling option models effective rolling resistance rather than detailed rotational inertia.
Run this experiment →A spring balance holds a block at rest on a frictionless incline. Plot holding force against sine of the incline angle to obtain a straight line of slope mg.
Run this experiment →Choose the scale span and number of equal divisions before reading an object. Smaller divisions improve resolution only when the marks can be distinguished.
Run this experiment →Support a metre scale at its own centre of mass so its weight creates no moment. Adjust suspended masses or pivot distances to balance clockwise and anticlockwise moments.
Run this experiment →Select graph scale through the measured range, correct a systematic zero shift and compare resolution bounds with inferred slope. The plotted staircase shows finite instrument divisions.
Run this experiment →Keep launch speed constant and sweep the protractor angle. Range peaks at 45° when launch and landing heights match. Complementary angles give equal ranges.
Run this experiment →Release a cart from rest on one slope and measure the rise on the second. Without losses it regains its original height irrespective of slope; friction lowers the return height.
Run this experiment →Track successive maximum swings to see energy lost to damping. Energy falls with the square of amplitude; the light-damping period is approximated by the small-angle undamped period.
Run this experiment →Use a long thin wire to make elastic extension measurable. Diameter enters as a square, so its measurement strongly affects the inferred modulus.
Run this experiment →Add loads and plot extension against force. A straight line through the corrected origin is the Hooke-law range. No-load inference is intentionally undefined and indicated as zero.
Run this experiment →Compress a sealed syringe slowly while holding temperature fixed. Its absolute pressure rises as volume falls; the PV product remains constant.
Run this experiment →Read the meniscus height above the reservoir. A smaller bore produces greater rise. The detergent selector demonstrates reduced tension using an explicit calibration factor.
Run this experiment →Time a sphere only after it has reached terminal speed. Stokes law applies when Reynolds number is much smaller than one; the readout explicitly flags choices outside that regime.
Run this experiment →Take temperature readings at equal time intervals and observe a decreasing slope as the body approaches room temperature. Correct a thermometer zero offset before fitting.
Run this experiment →Choose a solid sample or hot water and mix with cooler water. Include the calorimeter heat capacity so heat balance predicts the correct final temperature.
Run this experiment →Move sonometer bridges to set vibrating length and change the tension load. Match a tuning-fork frequency to the string resonance; frequency varies inversely with length and as square root of tension.
Run this experiment →Slide the water level to change the closed air column. Locate two resonance peaks; their separation removes the common open-end correction. Peak width is an illustrative apparatus response parameter.
Run this experiment →Follow cooling through a state change. Heat continues leaving during freezing while temperature remains near the model freezing point, because latent heat is released.
Run this experiment →Bonded layers want to expand by different amounts. Their mismatch bends the strip. Reversing temperature change or swapping expansion coefficients reverses the bend direction.
Run this experiment →Warm a liquid-filled vessel with a narrow capillary. The observed rise reflects liquid expansion minus vessel expansion, so apparent expansion is smaller than true expansion.
Run this experiment →Compare surface area, airflow represented by h and emissivity. Radiation uses absolute Kelvin temperature, while convection uses temperature difference. This apparatus study compares instantaneous heat-loss rates.
Run this experiment →Place a metre scale on two supports and add load at its midpoint. Depression grows with span cubed and decreases with thickness cubed; use modest loads within elastic bending.
Run this experiment →Narrowing a flowing tube raises speed and lowers pressure at equal height. Compare pressure-tube levels through the pressure-head readout; extreme invalid pressure predictions are flagged.
Run this experiment →Read voltage and current at several low-current settings and obtain resistance from the VI slope. Diameter measured with a screw gauge determines area; correct the ammeter zero.
Run this experiment →Slide the jockey until detector voltage reaches zero. Repeat with one resistor and its series or parallel combination; do not infer resistance from an unbalanced position.
Run this experiment →Adjust a shunt until deflection is half the unshunted reading. Then use the finite series-resistance correction to infer coil resistance and use original current per division for figure of merit.
Run this experiment →Choose the required range and derive the resistor to protect the sensitive coil. Check applied quantity against the chosen range before taking a reading; over-range values are visibly flagged.
Run this experiment →Tune the bridge spacing while keeping tension and density fixed. Resonance occurs when the wire natural frequency matches the force frequency. An unbiased AC electromagnet attracts on both current polarities.
Run this experiment →Compare current with and without the core at the same RMS voltage and frequency. The core raises inductance in this linear guide, increasing reactance and reducing current. Measure V/I rather than mistaking it for DC resistance.
Run this experiment →Meter function and connection must agree. Across-component voltage and series current are different measurements. Test continuity only in the source-off state, then compare a low resistance with an open component.
Run this experiment →Each branch switch controls its own parallel bulb, while the common fuse controls both. Current demand is the sum of branch currents. Changing voltage changes power through the fixed hot-resistance guide.
Run this experiment →Distinguish an open lead from a reversed source and a bypassed load. Correcting the selected fault restores the expected current. A negative meter reading can indicate reversed polarity rather than a failed load.
Run this experiment →Move the probe along the same wire and compare potential drop with distance. Uniform resistance per length gives a straight-line voltage gradient. The rheostat changes current and therefore the gradient.
Run this experiment →Move the screen until its distance agrees with the calculated real-image position. Record object and image distances, then estimate focal length. An object inside focus yields no sharp screen image.
Run this experiment →Use a convex lens to create a converging beam aimed at a point behind the convex mirror. Adjust mirror position until that point matches its centre of curvature. Normal incidence on the sphere makes rays retrace.
Run this experiment →Obtain different sharp u-v pairs by moving the object and screen. Their reciprocals lie on a line. Reading the intercept provides another focal-length estimate.
Run this experiment →A concave lens can yield a real final image when its incident beam is already converging sufficiently. The virtual-object distance must be signed, otherwise the focal calculation is wrong.
Run this experiment →Sweep incidence and identify the lowest deviation before using the prism-index formula. An angular zero error shifts the readings. An arbitrary deviation substituted for the minimum overestimates the index.
Run this experiment →Focus successively on the lower mark, upper surface and apparent lower mark. Differences remove the arbitrary reference reading. Resolution and focus error influence the resulting index ratio.
Run this experiment →Find the no-parallax needle distance in air and with the liquid layer. The liquid layer has negative power in this geometry. The focal change and known curvature give the liquid index.
Run this experiment →Reverse the virtual polarity and compare the voltage and current ranges. The resistor limits forward current. A reverse microamp reading is much smaller than the forward milliamps and needs a different meter scale.
Run this experiment →Inspect the specimen shape and decode its markings. Resistor bands and capacitor digits encode values in different units. A diode stripe identifies a terminal rather than a resistance multiplier.
Run this experiment →Use both lead orientations and compare silicon with an LED. A valid forward drop and reverse open indication are expected. An insufficient-compliance meter can show OL even for a working LED.
Run this experiment →Change distance while holding lamp output fixed. Illuminance falls with distance squared, while the resistance response is nonlinear. Read resistance rather than treating it as a direct light intensity.
Run this experiment →The two outside pin lines should be parallel. Measure their shortest separation, not their horizontal coordinate difference. Compare this shift with Snell’s law and correct an introduced ruler offset.
Run this experiment →Sweep the intensity probe and find the first minima on either side. Their separation measures central-maximum width. Repeat after changing slit opening while keeping wavelength and distance fixed.
Run this experiment →Change object location and move the screen to the real image. Lens and mirror send the outgoing light to opposite bench sides, even though their positive-distance equations share the same form.
Run this experiment →Compare contact and separated holders. Touching lenses add power; a gap changes the system power and principal-plane location. Equal positive and negative contact powers make an afocal pair.
Run this experiment →Read open-circuit voltage first, then close the load switch and observe terminal drop. Vary electrode spacing or immersed area to change internal resistance while holding the assigned EMF fixed.
Run this experiment →Keep distance fixed while varying lamp power. The calibration converts lamp watts into illuminance at the sensor; the LDR converts illumination into nonlinear resistance. Compare this investigation with the distance experiment.
Run this experiment →Compare voltage ratio with counted turns. A voltage step-up increases secondary voltage but decreases primary-to-secondary current ratio for conserved power. A load is needed to set actual current.
Run this experiment →Use the same prism angle for two fluids and retune incidence for each minimum. The larger-index liquid produces a larger minimum deviation. Prism walls must be accounted for in a real apparatus.
Run this experiment →A neutral ball is attracted by the nonuniform field through polarization. In the imposed contact state it receives the rod’s sign and repels. Increasing separation rapidly weakens the induced-force guide.
Run this experiment →Vary one geometric factor at a time. Turns enter quadratically; area and permeability linearly; length inversely. The negative induced emf expresses opposition to an increasing current.
Run this experiment →Align the coil plane with the magnetic meridian, then infer horizontal Earth field from the deflection. Deliberate misalignment demonstrates why the perpendicular-field condition matters.
Run this experiment →Raise the reverse source through breakdown while monitoring both meters. The diode voltage clamps approximately while resistor voltage and current increase. Compare two resistor settings at the same source.
Run this experiment →Move the viewpoint sideways, then adjust the image needle until relative motion vanishes. Coincidence identifies image distance without requiring a screen. A stationary view cannot distinguish aligned but separate planes.
Run this experiment →Choose ratio-arm plugs, adjust the standard box and watch galvanometer direction reverse through zero. A null means the bridge midpoint potentials agree. Use the chosen ratio to calculate the unknown.
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