BCS Written Physics case studies
BCS Written Physics · Put your knowledge to work in context.
The BCS Written Physics examination is the subject-specific written paper taken by candidates who have cleared the preliminary screening and are competing for cadre posts through Bangladesh's Civil Service examination system. It is intended for physics graduates and others with a strong physical-science background who want a government career, and it rewards candidates who can reason in equations and explain physical ideas in clear prose rather than simply recall facts. The BCS Written Physics case studies are 5 cases and about 3,375 words.
1Choosing a Working Fluid for a Solar Water Heater Loop
A workshop is retrofitting a flat-plate solar collector loop that must deliver heat to a 200 L tank. The pump can supply a pressure head of 12 kPa and the loop has an estimated hydraulic resistance of 3.5 kPa per (L/s)^2.
498 words, about 2 min2Interpreting a Discrepant g Measurement
A student measures g with a simple pendulum, timing 20 oscillations with a stopwatch for five lengths between 0.4 m and 1.0 m. She plots T^2 against L and obtains a gradient of 4.12 s^2/m with a stated uncertainty of ±0.06 s^2/m.
655 words, about 3 min3Diode Pump Versus Gravity Feed in a Micro-irrigation Line
A smallholder installs a drip line fed from a 1.5 m elevated tank through 30 m of 16 mm internal-diameter pipe, then a manifold with 20 emitters each rated 2 L/h at 100 kPa. The tank surface is open to atmosphere and the outlet is at the base.
730 words, about 4 min4Resolving a Line-Spectrum Puzzle in a Discharge Tube
Students view the emission from a low-pressure hydrogen discharge tube through a diffraction grating of 600 lines/mm and observe a violet line and a red line. They also see a faint yellow line that does not match the expected hydrogen series and a continuous background glow.
767 words, about 4 min5Deciding Whether a Resistivity Run Is Trustworthy
A student measures the resistivity of a semiconductor strip using the four-terminal method: a constant current of 1.00 mA is passed through the outer contacts, and the voltage across the inner contacts is read with a digital voltmeter of 10 MΩ input impedance. The strip is 10.0 mm long, 2.0 mm wide and 0.50 mm thick.
725 words, about 4 min