(A) Adding more water molecules
(B) Changing the motion of the water molecules
(C) Rearranging the atoms in water molecules
(D) Destroying the atoms in water molecules
Q. Water is a _______ most abundant molecule in the universe.
(A) second
(B) third
(C) fourth
(D) None of these
Q. The crystal structure of water is:
(A) Hexagonal
(B) Pentagonal
(C) Octagonal
(D) None of these
Answers:
1. (B) Changing the motion of the water molecules
2. (B) Third
3. (A) Hexagonal
(A) Gases do not conduct heat
(B) The best conductors are non-metals
(C) Conduction currents occur only in liquids
(D) None of the statements is true.
Q. The essence of the Kirchhoff’s law is that:
(A) A good absorber must be a bad radiator
(B) A good absorber must be a good radiator
(C) A good absorber must be a good conductor
(D) All are true
Q. A bad emitter of radiation is a bad absorber:
(A) True
(B) False
(C) Uncertain
(D) None of these
Answers:
1. (D) None of the statements is true
2. (B) A good absorber must be a good radiator
3. (A) True
(A) Aristotle
(B) Plato
(C) Newton
(D) Einstein
Answer:
(A) Aristotle
(A) -32°C
(B) 0°C
(C) 4°C
(D) 100°C
Q. As the temperature rises gradually, it’s surface tension:
(A) goes on increasing
(B) goes on decreasing
(C) remains unchanged
(D) increase only when the heat is too intense
Q. When a beam of light passes from air into water, its speed:
(A) increases
(B) decreases
(C) remains the same
(D) None of these
Answers:
1. (C) 4°C
2. (B) goes on decreasing
3. (B) decreases
(A) 300 million meters per second
(B) 300 million meters per hour
(C) 300 million kilometers per second
(D) 300 million kilometers per hour
Q. The speed of light in vacuum is a universal physical constant, commonly denoted by:
(A) s
(B) d
(C) c
(D) l
Q. Sunlight takes about _______ to travel the average distance from the surface of the sun to the Earth.
(A) 5 min 17 sec
(B) 6 min 17 sec
(C) 7 min 17 sec
(D) 8 min 17 sec
Answers:
1. (A) 300 million meters per second
2. (C) c
3. (D) 8 min 17 sec