1 |
Which part of the spectrum is most visible? |
Red
Violet
Yellow
Yellow-green
|
2 |
Finger prints on paper are identified by sprinkling fluorescent powder on it and observing it under |
Sun light
Sodium light
Infrared
UV
|
3 |
The image formed by an eyepiece of compound microscope is |
Real and diminished
Real and enlarged
Virtual and enlarged
Virtual and diminished
|
4 |
To get three images of a single object,one should have two plane mirrors at an angle of |
90°
120°
30°
160°
|
5 |
If red light is incident on sea water it appears |
Red
Green
Blue
Yellow
|
6 |
Which of the following colors suffers maximum deviation in a prism? |
Yellow
Blue
Green
Orange
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7 |
A diffraction pattern is obtained using a beam of red light What will happen if the red light is replaced by blue light? |
No change
Diffraction bands become narrower and crowded together
Bands become broader and farther apart
Bands disappear
|
8 |
Soap bubble looks colored due to |
Dispersion
Reflection
Interference
Any one of these
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9 |
Two sources of light are said to be coherent when the waves produced by them have |
Equal wavelength
Equal amplitude
Equal wavelength and constant phase difference
Amplitude and wavelength are same
|
10 |
If light of low wavelength is used in Young's double slit experiment then width of the fine will |
Decreases
Increase
Not fixed
No change
|
11 |
Two wave of intensities I an 4I superpose then the maximum and minimum intensities are |
5I and 3I
9I and I
9I and 3I
5I and I
|
12 |
Which does not show polarization? |
Longitudinal waves in gas
Transverse wave in gas
Both A and B
None of these
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13 |
If a lens is cut into two piece perpendicular to the principal axis and only part is used the intensity of the image: |
Remains same
1/2 times
2 times
Infinite
|
14 |
What is the main cause of the shinning of diamond? |
Reflection
Refraction
Total internal reflection
Dispersion of light
|
15 |
Which of the following spectrum have all the frequencies from high to low frequency range? |
Band spectrum
Continuous spectrum
Line spectrum
Discontinuous spectrum
|
16 |
All of the following statements are correct except |
The total focal length of an astronomical telescope is the sum of the focal lengths of its two lenses
The image formed by the astronomical telescope is always erect because the effect of the combination of the two lenses is divergent
The magnification of an astronomical telescope can be increased by decreasing the focal length of the eyepiece.
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17 |
The length of a telescope is 36 cm.The focal lengths of its lenses can be |
30 cm,6 cm
-30 cm,-6 cm
30 cm,-6 cm
-30 cm,-6 cm
|
18 |
To increase the magnification of a telescope |
The objective lens should be of large focal length and eyepiece should be of short focal length
The objective and eyepiece both should be of large focal lengths
Both the objective and eyepiece should be of smaller lengths
The objective should be small focal length and eyepiece should be of large focal length
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19 |
If tube length of astronomical telescope is 105 cm and magnifying power is 20 for normal setting calculate the focal length of objective |
100 cm
10 cm
20 cm
25 cm
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20 |
A planet is observed by an astronomical refracting telescope having an objective of focal length 16 m and an eyepiece of focal length 2 cm. |
The distance between the objective and the eyepiece is 8m
The angular magnification of the planet is 200
The image of the planet is inverted
The objective is smaller than the eyepiece
|