## Wednesday, April 24, 2019 # WBCS General Knowledge on General Science (Physics) P3

21. Consider the following statement1. Definition of force is obtained from Newton's first law of motion.2. Definition of force is obtained from Newton's second law of motion.3. In household writing, the appliances are connected in series.4. The picture-tube of television is basically a cathode ray tube.
(A) Only 2 and 4 are correct
(B) Only 1 and 4 are correct
(C) Only 1 is correct
(D) Only 2 is correct.
Correct Answer: [B] Only 1 and 4 are correct.

22. An ice cube containing a large bubble of air is floating in the water contained in a large breaker. When the ice melts completely, the level of water will
(A) Rise
(B) First rise and then go down
(C) Remain unchanged
(D) Go down.

23. Light-year is a unit of
(A) Light
(B) Intensity of light
(C) Time
(D) Distance.

24. A watch based on an oscillating spring is taken from the earth to the moon. It will -
(A) Give the same time
(B) Stop altogether
(C) Run slow
(D) Run fast.

25. A tube-well will not work if the depth of water below the ground is
(A) 28 ft.
(B) 38 ft.
(C) 20 ft.
(D) 25 ft.

26. A clear piece of glass immersed in glycerol cannot be seen separately because the comparison to the refractive index of glycerol, the refractive index of glass is
(A) Nearly equal
(B) This does not depend on the refractive index
(C) Greater
(D) Lesser.

27. The hydraulic breaks used in automobiles is a direct application of -
(A) Pascal's law
(B) Archimedes
(C) Bernoulli's theorem
(D) Torricelli law.

28. If a pendulum clock be taken from the equator to the poles, it will
(A) Given the same time
(B) stop altogether
(C) Run slow
(D) Run fast.

29. When a body is lifted by hand, what type of work is performed by hand?
(A) Third type of lever
(B) Simple machine
(C) First type of lever
(D) Second type of lever.
Correct Answer: [A] Third type of lever.

30. The same force is applied to two bodies A and B of masses m and 5m respectively for the same time. Then
(A) The momentum of A will be greater.
(B) The momentum of B will be greater.
(C) The velocity of A and B will be the same.
(D) The momentum of A and B will be the same.
Correct Answer: [D] The momentum of A and B will be the same..