Answer:
Option (C)
Explanation:
A metal detector is usually defined as an instrument that is commonly used to detect the presence of metals in the bags and luggage. It is very widely used in places like airports, railway stations, and other important official places.
This device is generally activated with the help of electromagnetic induction. It contains a single or numerous inducting coils which are connected to the elements placed on the ground surface. These used materials are metallic in nature. Within the region of the electromagnetic field, when any metallic substance enters, it immediately gains energy and thereby transmits an electromagnetic field of its own.
Thus, the correct answer is option (C).
MASS= Density times Volume
2.70*405
M= 1093.5
Answer: 
Explanation:
According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.
The balanced chemical reaction for nitrogen and hydrogen react to form ammonia:
(1)
The balanced chemical reaction for ammonia and oxygen react to form nitric acid and water:

(2)
The net chemical equation for the production of nitric acid from nitrogen, hydrogen and oxygen by adding 1 and 2
