GATE 2026 MN – Question 34

Surface Environment, Mine Ventilation and Underground Hazards · Mine Ventilation · 1 mark · Numerical answer

A Kata thermometer takes60 s to fall from38°C to35°C. Its factor is480 millicalories/cm². Find cooling power in W/m², to one decimal.

Practise this question in The GATE Grind →

Show answer and explanation

Correct answer: 334.0 to 337.0

Explanation

Cooling power is factor divided by time:480/60=8 millicalories/(cm² s). Convert1 millicalorie=0.004184 J and1 cm²=10⁻⁴ m². Thus power=8×0.004184/10⁻⁴=334.72 W/m², or334.7.

More Mine Ventilation questions

GATE 2026 MN Q40 – Two parallel ventilation districts A and B initially have common pressure drop ΔP and…
GATE 2026 MN Q52 – A mine fan generates25 mm water gauge and an aiding natural-ventilation pressure is15 mm…
GATE 2025 MN Q22 – A depillaring face has both dry- and wet-bulb temperatures of30°C. Find relative humidity…
GATE 2025 MN Q24 – Match fan-curve points P,Q,R to1 stall point,2 operating point,3 theoretical shut-off…
GATE 2025 MN Q32 – Airways of resistance4.0,6.25 and9.0 N s²/m⁸ are in parallel. Find equivalent resistance…
GATE 2025 MN Q40 – The airway is a rectangle topped by a semicircle of radius r. Its full perimeter is20 m…

All Mine Ventilation questions →