Physics
Radiocarbon is produced in the atmosphere as a result of

Lightning discharge in atmosphere.
Action of ultraviolet light from the sun on atmospheric oxygen.
Action of solar radiations particularly cosmic rays on carbon dioxide present in the atmosphere.
Collision between fast neutrons and nitrogen nuclei present in the atmosphere.

ANSWER DOWNLOAD EXAMIANS APP

Physics
It is easier to roll a stone up a sloping road than to lift it vertical upwards because

Work done in lifting the stone is equal to rolling it.
Work done in both is same but the rate of doing work is less in rolling.
Work done in rolling a stone is less than in lifting it.
Work done in rolling is more than in lifting.

ANSWER DOWNLOAD EXAMIANS APP

Physics
Siphon will fail to work if:

Both its limbs are of unequal length.
The level of the liquid in the two vessels are at the same height.
The temperature of the liquids in the two vessels are the same.
The densities of the liquid in the two vessels are equal.

ANSWER DOWNLOAD EXAMIANS APP