Answer the following questions: When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. Explain why?

In these question, a statement of asertion followed by a statement of reason is given .Choose the correct answer out of the following choices: Assertion and reason both are correct statements and reason is correct explanation for assertion. Assertion and reason both are correct statements but reason is not correct explanation for assertion. Assertion is correct statement but reason is wrong statement. Assertion is wrong statement but reason is correct statement. Assertion:When a tiny circular obstacle is placed in th path of light from some distance,a bright spot is seen at the cente of the shadow of the ostacle. Reason:Destructive interference occurs at the centre of the shadow.

Answer the following questions: Ray optics is based on the assumption that light travels in a straight line. Diffraction effects (observed when light propagates through small apertures/slits or around small obstacles) disprove this assumption. Yet the ray optics assumption is so commonly used in understanding location and several other properties of images in optical instruments. What is the justification?

Answer the following questions: Two students are separated by a 7 m partition wall in a room 10 m high. If both light and sound waves can bend around obstacles, how is it that the students are unable to see each. other even though they can converse easily.

Answer the following questions: When viewing through a compound microscope, our eyes should be positioned not on the eyepiece but a short distance away from it for best viewing. Why? How much should be that short distance between the eye and eyepiece?

These questions consist of two statements each,printed as Assertion and Reason.While answering these questions you are required to chose any one of the following four responses. If both Assertion and Reason are true and Reason in correct explanation of Assertion. If both assertion and Reason are true but reason is not correct explanation of Assertion. If Assertion is true but Reason is false. If both Assertion and Reason are false. Assertion:A man is blind for some time when he comes out of a well lighted room to a dark place. Reason:iodopsin of cone cells is bleached in the presence of strong light.

The question given below consist of an assertion (A) and a reason ( R). Use the following key to choose the appropriate answer to these questions from the codes (a), (b), ( c) and (d) given below: (a) Both A and R are true and R is the correct explanation of A. (b) Both A and R are true but R is NOT the correct explanation of A. (c) A is true but R is false. (d) A is false and R is also false. Assertion: When a charged particle moves in a circular path in a perpendicular magnetic field, the momentum of the charged particle remains constant. Reason: Velocity of the charged particle remains constant.

In these question, a statement of asertion followed by a statement of reason is given .Choose the correct answer out of the following choices: Assertion and reason both are correct statements and reason is correct explanation for assertion. Assertion and reason both are correct statements but reason is not correct explanation for assertion. Assertion is correct statement but reason is wrong statement. Assertion is wrong statement but reason is correct statement. Assertion:Newton's rings are formed in the reflected system.|When the space between the lens and the glass plate is filled with a liquid of refractive index gerter than that of glass,the central spot of the pattern in bright. Reason:This is because,reflections in these cases will be ffrom a denser to a rartrer medium and the two - interfering rays are reflected under siilar conditins.

These questions consist of two statement each, printed as Assertion and Reason. While answering these questions, you are required to choose any one of the following four responses. A. If both Assertion and Reason are true and Reason is a correct explanation of the Assertion. B. If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion. C. If Assertion is true but Reason is false. D. If both Assertion and Reason are false. Assertion: The quiescent centre acts as a reservoir of relatively resistant cells which consitute a permanent source of active initials. Reason. The cells of the inactive region of quiescent centre become active when the previous active initials get damaged.