Question

In Newton's Ring experiment with reflected light, the correct vertically downward arrangement of equipments is:
A. Microscope, Glass plate at \(45^\circ\), Plano-convex lens, Plane glass plate.
B. Plano-convex lens, Microscope, Plane glass plate.
C. Glass plate at \(60^\circ\), Microscope, Plano-convex lens.
D. Microscope, Plane glass plate, Plano-convex lens.

• A. A only
• B. B, C, D only
• C. B only
• D. C, D only

Hint:

In Newton's rings, the plano-convex lens is placed on a plane glass plate and rings are observed through a microscope.

Answer 1

The Correct Option is A

Concept:
Newton's rings experiment in reflected light uses a microscope, an inclined glass plate, a plano-convex lens and a plane glass plate.

Step 1: Identify the topmost instrument.
The microscope is placed at the top to observe the rings. \[ \text{Top}= \text{Microscope} \]

Step 2: Identify the reflecting plate.
A glass plate inclined at \(45^\circ\) reflects light towards the plano-convex lens arrangement. \[ \text{Next}=45^\circ \text{ glass plate} \]

Step 3: Identify the ring forming setup.
The plano-convex lens is placed on the plane glass plate. \[ \text{Plano-convex lens above plane glass plate} \]

Step 4: Final arrangement. \[ \text{Microscope} \rightarrow 45^\circ \text{ glass plate} \rightarrow \text{Plano-convex lens} \rightarrow \text{Plane glass plate} \] \[ \therefore \text{Correct Answer is (A)} \]