Find the radius of the central dark Newton's ring observed in reflection if there is benzene solution (n-1.5) filled in between lens and glass slab. Radius of curvature of the lens R-1 m. Indices of refraction of the lens and the glass slab are equal and higher than that of benzene. Yellow monochromatic light λ=5890 A is used.

That would be the corect answer hope this

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Answer: 1.4 seconds which is the third optionexplanation: current is defined as the flow of charge per timetherefore, the equation that relates current, charge and time can be expressed as follows: i = δq / δtwhere: i is the current given = 1.8 ampereδq is the charge given = 2.5 coulombδt is the time required for the flow of the given charges to give the 1.8 ampere.substitute with the givens in the above equation to get the time as follows: 1.8 = 2.5 / δtδt = 2.5 / 1.8 = 1.38888 which is approximately 1.4 secondshope this was !