Tarnishing of silver occurs due to its reaction with hydrogen sulfide (H₂S) gas present in moist air. This results in the formation of a black coating of silver sulfide (Ag₂S) on the surface of the silver object: \[ 2Ag + H_2S \rightarrow Ag_2S + H_2 \] This black layer of Ag₂S is what causes the silver spoon to appear tarnished.
The correct option is (B): \(Ag_2S\)
A force of \( P = 100 \, {N} \) is applied at the ends of the pliers as shown in the figure. Neglecting friction, the force exerted by the upper jaw on the workpiece is ........... N (in integer).
Consider a beam with a square box cross-section as shown in the figure. The outer square has a length of 10 mm. The thickness of the section is 1 mm. The area moment of inertia about the x-axis is ........... mm\(^4\) (in integer). 