Light, Sound and Heat TNPSC Group 1 Questions

Light, Sound and Heat MCQ Questions

13.
Through a soap film, different colours are seen by white light because of the phenomenon of
A.
Interference
B.
Reflection
C.
Diffraction
D.
Dispersion
ANSWER :
A. Interference
14.
A decibel is
A.
the relative intensity of sound
B.
unwanted noise
C.
a magnetic assembly in a tape
D.
the arm of a record-player
ANSWER :
A. the relative intensity of sound
15.
Optical fibre works on the principle of
A.
total internal reflection
B.
Refraction of light
C.
Scattering of light
D.
Interference of light
ANSWER :
A. total internal reflection
16.
The colour of an opaque object is due to the colour it
A.
absorbs
B.
refracts
C.
reflects
D.
scatters
ANSWER :
C. reflects
17.
Reed instrument without pipe is
A.
Trumpet
B.
Harmonium
C.
Flute
D.
Natheswaram
ANSWER :
B. Harmonium
18.

Arrange the following colours in increasing order of wavelength

i) orange

ii) indigo

iii) yellow

iv) violet

A.

I,ii,iii,iv

B.

I,ii,iv,iii

C.

iv,ii,iii,i

D.

ii,iv,I,iii

ANSWER :

C. iv,ii,iii,i