How does the Isotope of Iodine, Iodine-135 plays an important role in Nuclear Power Generation?

A. It is used as a fuel supplement in some of the modern Nuclear Reactors
B. It is a bi-product of Nuclear Reaction which kills the neutrons and this inhibits the power formation
C. It is a moderator used actively in the Nuclear Reactors
D. It is an experimental substance for Nuclear Fusion
✅ The correct answer is option B.

A long Rail (approximately 700 meters) made up of steel is struck to produce a sound. The person standing on the other end of the rail would hear in which among the following pattern?

A. He listens the sound waves once propagated via steel
B. He listens the sound waves once propagated via air
C. He listens the sound waves twice, first propagated via steel and second propagated via air
D. He listens the sound waves twice, first propagated via air and second propagated via steel
✅ The correct answer is option C.