TN State Board Samacheer Kalvi Online Test for 7th Std - Science - English - Optics

Question 1 Of 10

Magnification of a convex lens is

positive negative either positive or negative zero

Question 2 Of 10

A convex lens forms a real, diminished point-sized image at focus. Then the position of the object is at

focus infinity at 2f between f and 2f

Question 3 Of 10

If VB, VG, VR be the velocity of blue, green and red light respectively in a glass prism, then which of the following statement gives the correct relation?

VB = VG = VR VB > VG > VR VB < VG < VR VB < VG > VR

Question 4 Of 10

The refractive index of four substances A, B, C, and D are 1.31, 1.43, 1.33, and 2.4 respectively. The speed of light is maximum in

A B C D

Question 5 Of 10

In a myopic eye, the image of the object is formed

behind the retina on the retina in front of the retina on the blind spot

Question 6 Of 10

Where should an object be placed so that a real and inverted image of the same size is obtained by a convex lens

f 2f infinity between f and 2f

Question 7 Of 10

Power of a lens is –4D, then its focal length is

4m –40 m –0.25 m –2.5 m

Question 8 Of 10

A small bulb is placed at the principal focus of a convex lens. When the bulb is switched on, the lens will produce

a convergent beam of light a divergent beam of light a parallel beam of light a coloured beam of light

Question 9 Of 10

Which of the following lens would you prefer to use while reading small letters found in a dictionary?

A convex lens of focal length 5 cm A concave lens of focal length 5 cm A convex lens of focal length 10 cm A concave lens of focal length 10 cm

Question 10 Of 10

The eye defect ‘presbyopia’ can be corrected by

convex lens concave lens convex mirror bifocal lenses

Tamil Nadu State Board ( Samacheer Kalvi ) Online Test based on Book Back Questions - 7th Standard Science - English Medium - Optics

Samacheer Kalvi 7th Science - Optics - Book Back Questions in English Medium