The image for the converging beam after refraction through the curved surface is formed at:

               

1.  x = 40 cm

2.  $\mathrm{x} = \frac{40}{3}\mathrm{cm}$

3.  $\mathrm{x} = -\frac{40}{3} \mathrm{cm}$

4.  $\mathrm{x} = \frac{180}{7} \mathrm{cm}$

The dispersion of light in a medium implies that:

1.  Lights of different wavelength travel with different speed in the medium

2.  Lights of different frequencies travel with different speeds in the medium

3.  The refractive index of the medium is different for different wavelength

4.  All of the above

Which of the following diagrams shows correctly the dispersion of white light by a prism?

Statement I: A piece of paper placed at the position of a real image of a virtual object of intense light burns after sufficient time.

Statement II: A virtual object is that point where the incident rays appear to converge and a real image is that point at which reflected/ refracted rays actually converge.

1.  Statement 1 is true, statement 2 is true; statement 2 is the correct explanation for statement 1

2.  Statement 1 is true, statement 2 is true; statement 2 is NOT correct explanation for the statement 1

3.  Statement 1 is true, statement 2 is false.

4.  Statement 1 is false, statement 2 is true.

A person’s eye is at a height of 1.5 m. He stands in front of a 0.3 m long plane mirror  whose lower edge is 0.8 m above the ground. The length of the image he sees of himself is:

1.  1.5 m 

2.  1.0 m

3.  0.8 m 

4.  0.6 m

A dentist has a small mirror of focal length 16 mm. He views the cavity in the tooth of a patient by holding the mirror at a distance of 8 mm from the cavity. The magnification is:

1.  1

2.  1.5

3.  2

4.  3

A fish is a little away below the surface of a lake. If the critical angle is 49°, then the fish could see things above Water surface within an angular range of $\mathrm{\theta }$° where:

1.  $\mathrm{\theta } = 49°$

2.  $\mathrm{\theta } = 98°$

3.  $\mathrm{\theta } = 24\frac{1}{4}°$

4.  $\mathrm{\theta } = 90°$

In order to obtain a real image of magnification 2, using a converging lens of focal length 20 cm, where should an object be placed:

1.  50 cm

2.  30 cm

3.  - 50 cm

4.  - 30 cm

The focal lengths for violet, green, and red light rays are ${\mathrm{f}}_{\mathrm{V}}, {\mathrm{f}}_{\mathrm{G}}, \mathrm{and} {\mathrm{f}}_{\mathrm{R}}$ respectively. Which of the following is the true relationship?

1.  ${\mathrm{f}}_{\mathrm{R}}$ < ${\mathrm{f}}_{\mathrm{G}}$ < ${\mathrm{f}}_{\mathrm{V}}$

2.  ${\mathrm{f}}_{\mathrm{V}}$ < ${\mathrm{f}}_{\mathrm{G}}$ < ${\mathrm{f}}_{\mathrm{R}}$

3.  ${\mathrm{f}}_{\mathrm{G}}$ < ${\mathrm{f}}_{\mathrm{R}}$ < ${\mathrm{f}}_{\mathrm{V}}$

4.  ${\mathrm{f}}_{\mathrm{G}}$ < ${\mathrm{f}}_{\mathrm{V}}$ < ${\mathrm{f}}_{\mathrm{R}}$

A plane mirror is placed at the bottom of a tank containing a liquid of refractive index $\mathrm{\mu }$. P is a small object at a height h above the mirror. An observer O vertically above P outside the liquid sees P and its image in the mirror. The apparent distance between these two will be:

1.  $2\mathrm{\mu h}$

2.  $\frac{2\mathrm{h}}{\mathrm{\mu }}$

3.  $\frac{2\mathrm{h}}{\mathrm{\mu } - 1}$

4.  $\mathrm{h}\left(1 + \frac{1}{\mathrm{\mu }}\right)$