Question

Q11 A ray of light parallel to the principal axis of a concave mirror,after reflection, passes through *

Centre of curvature

Pole

Focus

Q12 A concave mirror ______ the Ray's of light falling on it *

Converges

Diverges

Has no effect

Q13 A ___ image cannot be obtained on a screen *

Virtual

Real

Magnified

Q14 The speed of sound in solid is greater then that in a liquid *

True

False

Q15 The audible range of sound for human beings is *

Less then 20Hz

Between 20Hz and 20kHz

More then 20,000Hz

Q16 Sonography technique uses probe and gel *

False

True

Q17 Three mirrors are created from a single sphere ,then __ will be common to them *

Pole

Principal axis

Centre of curvature

Q18 The 2 mirrors in a periscope are placed parallel to each other ,so that*

The location of object can be seen clearly

Many images can be seen of the object

Q19 The function of cochlea in inner ear is *

Produce vibration in eardrum

Receives vibrations and converts to electrical signals

Detects loudness of sound

Q20 In case of image formation of a concave mirror ,state the position and type of image formed if the object is between C and F

Image is real,inverted ,enlarged and beyond C

Image is real ,inverted ,enlarged and formed at C​

Answer 1

Answer:

11. Focus.

12. Converges.

13. virtual.

14. True.

15. between 20Hz and 20kHz.

16.True

17. centre of curvature.

18.the location of the image can be seen clearly.

19. receive vibration and convert into electric signal.

20. image is real, inverted, enlarged and beyond the C .

Hope it helps you

plz make brilliant.