Exercise

The picture shows the incomplete chain structure of a carbon compound. The second carbon atom has two free electrons.

How many oxygen atoms can combine with the second carbon atom to complete the structure?

Which of these molecules contains a double bond?

The picture shows the path of light as it travels from one medium to another.

What is medium 1 and medium 2?

The power of a lens $\left(P\right)$ is calculated by the formula: $P= \frac{1}{f}$, where $f$ is the focal length of the lens. A lens has a focal length of $– 0.25 \mathrm{m}$. Is it a convex lens or a concave lens? Explain your answer.

When an incident ray of light enters a medium from the air, it bends towards the normal. Which of the following is TRUE about the refractive index of the medium ($n_m$) as compared to the refractive index of air ($n_a$)?

The diagram below shows the image of a candle, as formed through refection from a concave mirror, obtained on a screen.

How many light rays from the point P on the candle flame can be drawn to the corresponding point on the image P'?

The images formed by an ordinary convex lens suffer from a defect, called chromatic defect, which leads to false coloured edges in the images. This happens because light rays of different colours bend differently as they enter and leave the lens.

If a parallel white light beam passes through a convex lens, the light of which colour (among violet to red in the spectrum) will converge at a point closest to the lens? Justify your answer.

A lens made of material with a refractive index $1.5$ is immersed in a liquid with a refractive index $1.5$. The diagram below shows two rays incident on the lens when it is immersed in the liquid.

Copy the diagram and draw the light rays after they pass through the lens. Justify your diagram.