## Wednesday, April 24, 2019 # General Science MCQs for WBCS, SSC, RAIL, State PSC, UPSC P9

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159381. With an increase in temperature the resistance of a pure semiconductor
A
increases
B
decreases
C
first increases and then decreases
D
remains the same
B
149282. Dentists use this mirror. Dentists use
A
Concave Mirror
B
Convex
C
Special Mirror
D
Plane Mirror
A
146183. When an object is placed between two parallel mirrors, the number of images formed will be
A
Thirty-Two
B
Infinite
C
Eight
D
Two.
B
150984. The nature of the motion of a sewing machine is
A
Oscillatory motion
B
Rotational motion
C
Circular motion
D
Translational motion
A
147585. Consider the following statement 1. 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.
B
Correct Answer: B. Only 1 and 4 are correct
154486. The heat of the sun reaches us by
A
B
Convection
C
Conduction
D
None of the above
A
256087. Size of the sun is how many times bigger than that of the earth?
A
124 times
B
100 times
C
109 times
D
115 times
C
150188. Einstein was awarded the Nobel Prize for
A
General theory of relativity
B
Explanation of Brownian motion
C
Photoelectric emission
D
Special theory relativity.
C
147189. Which one of these is not a measuring instrument?
A
Picometer
B
Hygrometer
C
Barometer
D
Thermometer.
A
Explanation:
• A picometer is a unit of measurement of length. A picometer (pm) is a derived metric measurement unit of length. The metric unit prefix pico means one trillionth, or one (1) with eleven (11) nulls in front of it, i.e. 0.000,000,000,001 or 1×10-12. That makes one picometer equal to one trillionth of a meter.
• Hygrometer, an instrument used in meteorological science to measure the humidity or amount of water vapor in the air.
• A barometer is a scientific instrument used to measure atmospheric pressure, also called barometric pressure.
• A thermometer is a device that measures temperature or a temperature gradient (the degree of hotness or coldness of an object).
147990. 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.
A