TNUSRB Constable: General Science for TNUSRB Constable

General Science in this paper is school-level physics, chemistry and biology, plus health and environment facts. Most questions ask you to identify, match or apply one rule; numerical work rarely goes beyond a single step.

High-yield clusters

• SI units: force in newton (N), work and energy in joule (J), power in watt (W), pressure in pascal (Pa), frequency in hertz (Hz).
• Vitamins and deficiency: A - night blindness; B1 - beriberi; C - scurvy; D - rickets; K - poor blood clotting.
• Blood: groups A, B, AB and O; O negative is the universal donor, AB positive the universal recipient; haemoglobin carries oxygen.
• Photosynthesis: 6CO2 + 6H2O → C6H12O6 + 6O2, in the presence of chlorophyll and sunlight.
• Acids turn blue litmus red, bases turn red litmus blue; pH below 7 is acidic, above 7 basic.

Worked example

A car covers 90 km in 1 hour 30 minutes. Find its average speed in m/s. Speed = distance ÷ time = 90 ÷ 1.5 = 60 km/h. To convert, multiply by 5/18: 60 × 5/18 = 16.67 m/s. Remember the factor runs both ways - km/h to m/s is × 5/18, m/s to km/h is × 18/5.

Traps that cost marks

Students reverse the universal donor and recipient; write the photosynthesis equation without chlorophyll; and forget that mass stays constant while weight changes with gravity. Unit symbols also matter: kg, m and s are lower case, while N and J are capitals. In biology, do not confuse the largest gland (liver) with the largest organ (skin).