 General Knowledge Questions for CDS & AFCAT: 21st December Dear Students, Defence Adda is providing you all with this quiz on General Knowledge questions for CDS, AFCAT, CAPF and other Defence Examinations.

Q1. Instrument for measuring rainfall is called -
(a) Lucimeter
(b) Galactometer
(c) Hyetometer
(d) Hygrometer

Q2. Who established the foundations of the quantum theory?
(a) Max Planck
(b) Mark Nicholas
(c) Albert Einstein
(d) Alfred Hitchcock

Q3. If in a motion, the axis of the rotation passes through an object, the motion is called _________.
(a) Orbital motion
(b) Circulatory motion
(c) Spin motion
(d) Oscillatory motion

Q4. If an object, on a free fall from a certain height, reaches the ground in 1 second, what is its velocity on the impact with the ground?
(a) 4.9 m/s
(b) 9.8 m/s
(c) 14.7 m/s
(d) 19.6 m/s

Q5. What is the angle between centripetal acceleration and tangential acceleration?
(a) 90°
(b) 45°
(c) 0°
(d) 180°

Q6. Rectifiers convert _____.
(a) high voltage to low voltage
(b) low voltage to high voltage
(c) AC to DC
(d) DC to AC

Q7. Name the first Indian who got Nobel Prize in physics.
(a) C K Naidu
(b) Rangnath Mishra
(c) Amartya Sen
(d) C V Raman

Q8. Which physical quantity is measured in 'siemens'?
(a) Electric potential
(b) Electrical conductance
(c) Magnetic flux
(d) Refractive index

Q9. For which of the following game, players must have the knowledge of Pascal's law?
(a) Climbing
(b) Paragliding
(c) Rafting
(d) Scuba diving

Q10. What is the value of the Least Distance of Distinct vision (in cm) for a normal human being?
(a) 2.5
(b) 25
(c) 58
(d) 60

Q11. Who invented the Centigrade scale?
(a) Anders Celsius
(b) Daniel Gabriel Fahrenheit
(c) William Thomson
(d) Wright Brothers

Q12. On which principle does the hydraulic lift works?
(a) Newton's law
(b) Pascal's law
(c) Archimedes's law
(d) Joule's law

Q13. The coil wire in the electric room heater or electric cooking heater is called __________.
(a) Circuit
(b) Element
(c) Filament
(d) Cells

Q14. Energy in the form of heat is wasted when a machine is operated. This heat is generated due to ___________.
(a) Burning
(b) Friction
(c) Combustion
(d) Lubrication

Q15. The incident ray, the _________ at the point of incidence and the reflected ray all lie in the same plane.
(a) Surface
(b) Tangent
(c) Normal
(d) Angle of reflection

SOLUTIONS

S1. Ans.(c)
Sol. Hyetometer is the instrument used to measure rainfall.

S2. Ans.(a)
Sol. Max Planck was a German theoretical physicist, considered to be the initial founder of quantum theory, and one of the most important physicists of the 20th Century.

S3. Ans.(c)
Sol. In physics, spin is the velocity of rotation of something around a particular axis.

S4. Ans.(b)
Sol. If an object, on a free fall from a certain height, reaches the ground in 1 second, its velocity on the impact with the ground 9.8 m/s.

S5. Ans.(a)
Sol. The angle between centripetal acceleration and tangential acceleration is 90°.

S6. Ans.(c)
Sol. A rectifier is an electrical device composed of one or more diodes that converts alternating current (AC) to direct current (DC).

S7. Ans.(d)
Sol. The Nobel Prize in Physics 1930 was awarded to Sir Chandrasekhara Venkata Raman "for his work on the scattering of light and for the discovery of the effect named after him.

S8. Ans.(b)
Sol. The Siemens (symbol S) is the derived unit of electric conductance.

S9. Ans.(d)
Sol. Pascal's principle states that "a change in the pressure of an enclosed incompressible fluid is conveyed undiminished to every part of the fluid and to the surfaces of its container." For every 10m depth the pressure on the diver increases by 1 atm so at a depth of 10 meters under water, pressure is twice the atmospheric pressure at sea level. Thus, during Scuba diving players must have the knowledge of Pascal’s law.

S10. Ans.(b)
Sol. Least distance of distinct vision is defined as the minimum distance between the eye lens and the object to form a clear image. For a healthy human eye, the least distance of distinct vision is 25 cm, however it varies with age.

S11. Ans.(a)
Sol. In 1742, Swedish astronomer, Anders Celsius invented the Celsius(Centigrade) temperature scale, which was named after the inventor.

S12. Ans.(b)
Sol. Pascal's Law states that pressure that is applied to an enclosed fluid is transmitted equally to all other points. A hydraulic pump is a water pump that uses the kinetic energy of flowing water to force a small fraction of that water to a reservoir at a higher level. The hydraulic lift works because of Pascal’s law. If force is put on(according to Pascal’s Law), that force should be entirely felt on all points throughout the liquid.

S13. Ans.(b)
Sol. The coil wire is heating element in electric room heater or electric cooking heater to converts electricity into heat through the process of resistive or Joule heating. Electric current passing through the element encounters resistance, resulting in heating of the element.

S14. Ans.(b)
Sol. Energy in the form of heat is wasted when a machine is operated. This heat is generated due to Friction between two parts.

S15. Ans.(c)
Sol. The law of reflection states that the incident ray, the reflected ray, and the normal at the point of incidence all lie in the same plane.