Diamond is a very expensive ornament. It is composed of a single element ___________?
A. Carbon
B. Gold
C. Silver
D. Platinum
E. None of these
Which of the following layers make radio transmission possible?
A. Troposphere
B. Ionosphere
C. Mesosphere
D. Stratosphere
E. None of these
Which of the following explains the reason why there is no total eclipse of the sun?
A. Size of the earth in relation to that of moon
B. Orbit of moon around earth
C. Direction of rotation of earth around sun
D. Area of the sun covered by the moon
E. None of these
Television signals are converted into light signals by___________?
A. Optical fiber
B. Transistor
C. Decoder
D. Photo diode
E. None of these
Where do most of Asteroids lie?
A. In asteroid belt between the orbits of Mars and Jupiter
B. In asteroid belt between the orbits of Mars and Venus
C. In asteroid belt between the orbits of Jupiter and Venus
D. Everywhere in the sky
E. None of these
The number of spark plugs needed in a diesel engine is__________?
A. 2
B. 3
C. 0
D. 4
E. None of these
The half life of a radioactive element is 8-days. How long it take to reduce it from 10 mg to 5 mg?
A. 4 days
B. 12 days
C. 16 days
D. 8 days
E. None of these