81- Consider the following statements about vapour lasers:
Though originally invented in 1966, they are now being developed further for a wide variety of applications because:
1. They can produce short and long wavelength radiation.
2. They can be focused on very small areas.
3. Of their very high frequency and narrow pulse-widths.
A. 1 and 2
B. 2 and 3
C. 1 and 3
D. 1, 2 and 3
View Answer
Answer : D. 1, 2 and 3
Description
82- Enriched uranium used in a nuclear reactor is:
A. Uranium treated with radiation
B. Uranium freed of all impurities
C. Uranium alloyed with aluminium
D. Uranium with a high percentage of a particular isotope
View Answer
Answer : D. Uranium with a high percentage of a particular isotope
Description
83- The main important feature of neutron bomb is that when it is dropped on a city it would damage:
A. Both the living organisms and buildings
B. The buildings but not the living organisms
C. The living organisms but spare buildings
D. None of these
View Answer
Answer : C. The living organisms but spare buildings
Description
84- Which of the following shows the masses of the elementary particles in decreasing order?
A. Baryons, Mesons, Leptons
B. Leptons, Mesons, Baryons
C. Mesons, Baryons, Leptons
D. Leptons, Baryons, Mesons
View Answer
Answer : A. Baryons, Mesons, Leptons
Description
85- Hydrometer is an instrument:
A. For measuring sound under water
B. To detect the presence of hydrogen in the atmosphere
C. To detect the changes in atmospheric humidity
D. For measuring the specific gravity of liquids
View Answer
Answer : D. For measuring the specific gravity of liquids
Description
86- Which thermometer is used to indicate the lowest temperature?
A. Clinical thermometer
B. Gas thermometer
C. Alcohol thermometer
D. Resistance thermometer
View Answer
Answer : C. Alcohol thermometer
Description
87- One horse power is equal to:
A. 736 watts
B. 746 watts
C. 748 watts
D. 756 watts
View Answer
Answer : B. 746 watts
Description
88- Bar is the unit of:
A. Heat
B. Temperature
C. Current
D. Atmospheric pressure
View Answer
Answer : D. Atmospheric pressure
Description
89- A chronometer measures:
A. Time
B. Sound waves
C. Water waves
D. Colour contrast
View Answer
Answer : A. Time
Description
90- One fathom is equal to:
A. 6 Feet
B. 10 feet
C. 60 feet
D. 100 cms
View Answer
Answer : A. 6 Feet
Description
91- What is the number of basic units in the International System of Units?
A. 4
B. 5
C. 6
D. 7
View Answer
Answer : D. 7
Description
92- What is the unit for measuring the pitch or frequency of sound?
A. Hum
B. Hertz
C. Decibel
D. Coulomb
View Answer
Answer : B. Hertz
Description
93- Knot is a unit of speed of which of the following?
A. Ship
B. Light waves
C. Sound waves
D. Aeroplane
View Answer
Answer : A. Ship
Description
94- Electric current is measured by:
A. Voltmeter
B. Ammeter
C. Conductor
D. Anemometer
View Answer
Answer : B. Ammeter
Description
95- The dynamo is a device for converting:
A. Magnetic energy into electrical energy
B. Chemical energy into electrical energy
C. Heat energy into electrical energy
D. Mechanical energy into electrical energy
View Answer
Answer : D. Mechanical energy into electrical energy
Description
96- Fathom is the unit of:
A. Depth
B. Sound
C. Distance
D. Frequency
View Answer
Answer : A. Depth
Description
97- Which of the following is a flightless bird?
A. Emu
B. Hen
C. Swan
D. None of these
View Answer
Answer : A. Emu
Description
98- Which of the following instruments is used for precise measurement of refractive indices?
A. Spherometer
B. Micrometer
C. Spectrometer
D. Photometer
View Answer
Answer : C. Spectrometer
Description
99- Kilohertz is a unit which measures:
A. Electric resistance
B. Power used by a current of one ampere
C. Electromagnetic radio wave frequencies
D. None of these
View Answer
Answer : C. Electromagnetic radio wave frequencies
