General Knowledge Quiz (Previous Years) for NDA & Other Defence Exams: 15th April

Dear Students, Defence Adda is providing you all with this quiz on General Knowledge questions for NDA & Other Defence Exams.

Q1. Flow velocities in an incompressible fluid can be measured with which one of the following?
(a) Barometer
(b) Venturi tube
(c) Strain gauge
(d) Manometer

Q2. A syringe is a hollow glass tube with lower end tapered to a nozzle. Due to which one of the following liquids can be drawn into a syringe?
(a) Partial vacuum produced inside the glass tube
(b) Diffusion
(c) Surface tension effect
(d) Capillary action

Q3. The mass of water vapor per unit volume of air is known
(a) relative humidity
(b) specific humidity
(c) absolute humidity
(d) variable humidity

Q4. Kinetic viscosity of a given liquid is the ratio of the
(a) coefficient of viscosity to the density
(b) coefficient of viscosity to the surface tension
(c) density to the coefficient of viscosity
(d) surface tension to the coefficient of viscosity

Q5. When oil floats on water, the surface tension of water
(a) vanished immediately
(b) decreases considerably
(c) increases considerably
(d) remains unaffected

Q6. Consider two hollow glass spheres, one containing water and the other containing mercury. Each liquid fills about one-tenth of the volume of the sphere. In zero gravity environment
(a) water and mercury float freely inside the sphere
(b) water forms a layer on the glass, while mercury floats
(c) mercury forms a layer on the glass, while water floats
(d) water and mercury both form a layer on the glass

Q7. The density of cast iron having specific gravity 7.20 is
(a) 7.20 kg/m³
(b) 720 kg/m³
(c) 72 kg/m³
(d) 7200 km/m³

Q8. A vessel contains oil density 0.8 gm/cm³ over mercury of density 13.6 gm/cm³. A homogeneous sphere floats with half of its volume immersed in mercury and the other half in half of its volume immersed in mercury and the other half in oil. The density of the material of the sphere in CGS unit is
(a) 3.3
(b) 6.4
(c) 7.2
(d) 12.8

Q9. Water flows out of the hole of a bucket and follows a parabolic path. If the bucket falls freely under gravity, the water flow (ignoring air resistance)
(a) follows a straight-line path relative to the falling bucket
(b) follows a parabolic path relative to the falling bucket
(c) stops
(d) decreases but continues to flow

SOLUTIONS

S1. Ans.(b)
Sol. Barometer, venturi meter, Strain Gauge and Manometer are used to measure atmospheric pressure, velocity of an in-compressible fluid, strain and pressure respectively.

S2. Ans.(a)
Sol. When piston is pulled, partial vacuum is created inside the tube due to which pressure becomes negligible and hence the liquid enters the tube because of its pressure.

S3. Ans.(c)
Sol. The absolute humidity may be defined as the mass of water vapor per unit volume of air.

S4. Ans.(c)
Sol. Kinetic viscosity of given liquid is the ratio of the density to the coefficient of viscosity.

S5. Ans.(b)
Sol. When oil floats on water, the surface tension of water decrease considerably.

S6. Ans.(b)
Sol. In zero gravity environment water forms a layer on the glass, while mercury floats.

S9. Ans.(b)
Sol. If the bucket falls freely under gravity, the water flow follows a parabolic path relative to the falling bucket.