Draw ray diagrams showing the image formation by a concave lens when an object is placed (c) beyond twice the focal length of the lens

Identify the device used as a spherical mirror or lens in following cases, when the image formed is virtual and erect in each case. (b) Object is placed between the focus and device, image formed is enlarged and on the same side as that of the object.

Q1.The angle of incidence is equal to the angle of reflection. This is known as:

A student focussed the image of a candle flame on a white screen using a convex lens. He noted down the position of the candle screen and the lens as under: Position of candle = 12.0 cm, Position of convex lens = 50.0 cm, Position of the screen = 88.0 cm. (i) What is the focal length of the convex lens?

Draw ray diagrams showing the image formation by a convex mirror when an object is placed (a) at infinity

You are given water, mustard oil, glycerine and kerosene. In which of these media a ray of light incident obliquely at same angle would bend the most?

Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of 15 cm from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?

Define power of a lens. What is its unit? One student uses a lens of focal length 50 cm and another of –50 cm. What is the nature of the lens and its power used by each of them?

Two thin lenses of power, + 3.5 D and, – 2.5 D are placed in contact. Find the power
and focal length of the lens combination.

The real image formed by a concave mirror is smaller than the object if the object is :

A convex lens of focal length 20 cm can produce a magnified virtual as well as real image. Is this a correct statement? If yes, where shall the object be placed in each case for obtaining these images?

Identify the device used as a spherical mirror or lens in following cases, when the image formed is virtual and erect in each case. (a) Object is placed between device and its focus, image formed is enlarged and behind it.

Which of the following ray diagrams is correct for the ray of light incident on a concave mirror as shown in Figure 10.6?

Size of image of an object by a mirror having a focal length of 20 cm is observed to be reduced to $frac{1}{3}$rd of its size. At what distance the object has been placed from the mirror? What is the nature of the image and the mirror?

Draw a ray diagram showing the path of rays of light when it enters with oblique incidence (i) from air into water;

Which of the following ray diagrams is correct for the ray of light incident on a lens shown in Fig. 10.7?

Draw ray diagrams showing the image formation by a concave mirror when an object is placed (e) at infinity

Under what condition in an arrangement of two plane mirrors, incident ray and reflected ray will always be parallel to each other, whatever may be angle of incidence. Show the same with the help of diagram.

Identify the device used as a spherical mirror or lens in following cases, when the image formed is virtual and erect in each case. (c) Object is placed between infinity and device, image formed is diminished and between focus and optical centre on the same side as that of the object.

A child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size and that of the legs smaller. The following is the order of combinations for the magic mirror from the top.