An object is placed well outside the principal focus of a convex lens. Draw a ray diagram to show how.

Draw ray diagrams showing the image formation by a concave mirror when an object is placed:
At centre of curvature of the mirror.

If a ray of light enters from alcohol to air. The refractive index of alcohol is 1.36. Calculate the speed of light in alcohol with respect to air.

Briefly describe how you would find the focal length of a concave mirror quickly but approximately.

State the uses of plane mirrors.

A convex lens forms a real and inverted image of a needle at a distance of 50 cm from it. Where is the needle placed in front of the convex lens if the image is equal to the size of the object? Also, find the power of the lens.

Draw a ray diagram to show the formation of a real magnified image by a convex lens. (In your sketch the position of object and image with respect to the principal focus of lens should be shown clearly).

What is observed when 2mL of dilute hydrochloric acid is added to 1g of sodium carbonate taken in a clean and dry test tube? Write chemical equation for the reaction involved.

How could you find the focal length of a convex lens rapidly but approximately?