31.Which of the following pairs is correctly matched?
1. a
2. b
3. c
4. d
Option “1” is correct. Radium is a chemical element discovered by Marie Curie and her husband Pierre Curie . Penicillin was discovered by Alexander Fleming . X-ray were discovered by William Roentgen . Edward Jenner is well known around the world for his innovative contribution to immunization and the ultimate eradication of smallpox.
32. While travelling by plane, the ink of the fountain pen starts to come out-
1. Due to decrease in air pressure
2. Due to increase in air pressure
3. Due to increase in volume of ink
4. Due to excessive load
Option “1” is correct. The fountain pen leak at high altitudes. It is because of low air pressure.
33.Match List-I with List-II and select the correct answer using codes given below:
1. a
2. b
3. c
4. d
Option “3” is correct. The SI unit of power is the Watt (w), which is equal to one joule per second. Knot is the unit of measuring of speed of a ship. Nautical mile is a unit of distance used by navigators in sea. Calorie is a unit of measuring heat and energy.
34. Which one of the following instrument is used for locating submerged objects in an ocean?
1. Audiometer
2. Galvanometer
3. Sextant
4. SONAR
Option “4” is correct. SONAR [Sound Navigation and Ranging is used for locating submerged objects in an ocean.
35. Which of the following is not a vector quantity?
1. Displacement
2. Velocity
3. Force
4. Volume
Option “4” is correct. A vector quantity is a quantity that is fully described by both magnitude and direction. On the other hand, a scalar quantity is a quantity that is fully described by its magnitude. Thus displacement, velocity and force are the example of vector quantity while volume is a scalar quantity.
36. Who gave the theory of gravity?
1. Charles Newton
2. Charles Babbage
3. Isaac Newton
4. John Adams
Option “3” is correct. In 1687, Isaac Newton published his Law of Gravitation in “Mathematical Principles of Natural Philosophy”. He gave the Theory of Gravity.
37. GPS stands for which one of the following?
1. Greenwich Polar Satellite
2. Global Police Surveillance
3. Global Positioning System
4. General Pacific Survey
Option “3” is correct. GPS means Global Positioning System, is a space-based navigation system. It was developed by the U.S. Department of defence.
38. Einstein was honoured with Nobel Prize for:
1. Photoelectric Effect
2. Theory of Specific Heat
3. Special Theory of Relativity
4. Bose-Einstein Statistics
Option “1” is correct. The Noble Prize in Physics in 1921 was awarded to Albert Einstein for his services to Theoretical Physics and especially for his discovery of the “Law of the Photoelectric Effect”.
39. Who is the discoverer of Penicillin?
1. Alexander Graham Bell
2. Alexander Fleming
3. Christopher Macdonald
4. Albert Einstein
Option “2” is correct. Penicillin was discovered by Scottish scientist Alexander Fleming.
40. The hand burns more by steam comparatively to boiling water, because-
1. The steam has latent heat
2. Steam sneaked into the body
3. The steam has more power
4. Steam is gig
Option “1” is correct. Steam has more heat energy than boiling water because it requires Latent Heat of Vapourization for boiling water to change phase from liquid to vapour. Therefore our body comes in contact with more heat when exposed to steam than boiling water
