HAL Quiz 2022 CE 1

A filter bed is composed of 12 inches of uniform anthracite with an average size of 1.6 mm for a filtration rate of 4 gal/ft²/min (or 160L/min/m²) (temperature is 20°C; particle shape factor: 0.50; kinematic viscosity: 1.091 x 10^-5 ft²/s). Calculate Reynolds number?

According to Khosla’s theory, the exit gradient in the absence of a downstream cutoff is:-

Which of the following is true in case of railway track maintenance?

A tower of height 200m is photographed using a camera of focal length 2.5cm from an altitude of 1250m. The relief displacement is 8 mm and the distance of the top of the tower from the principal point on the photograph is 12 mm.

It is observed that the aircraft is directly flying in the direction of the tower. If the speed of the aircraft is 180kmph, how long will it take for the aircraft to pass directly over the tower?

One liter of sewage, when allowed to settle for 30 minutes gives a sludge volume of 27 cm³. If the dry weight of this sludge is 3.0 grams, then its sludge volume index will be

Sensitivity of a modular outlet is equal to

The reception signal is

A camera of focal length 15 cm is used to take images of the ground at an altitude of 2100m from the mean sea level. The size of the photograph is 25 cm × 25 cm. The ground is at 300 m from the sea level and the area of the ground is 108 sqkm. If the longitudinal overlap is 60% and the side lap is 40%, find the number of photographs required.