Worksheetsphysics
Total questions: 10
Worksheet time: 8mins
1. A convergent lens is one which A convergent lens is one which -----------
Collect rays
spread rays
forms real image
forms virtual image
2. The unit of power of lens is -------
volt
ampere
watt
dioptre
3. The inability of lens to form the white image of a white object is -------------
spherical aberration
coma
chromatic aberration
astigmation
4. The spectral lines are dispersed by a prism to a larger extent near ------
the violet end of spectrum
the red end of spectrum
the prism
the telescope
5. The direct vision spectroscope is based on ---------
deviation without dispersion
dispersion without deviation
neither dispersion nor deviation
total internal reflection
6. The phenomenon of splitting of white light into constituent colours is ----
diffraction
polarization
interference
dispersion
7. For minimum spherical aberration, two lenses of focal lengths f1 and f2 are to be placed at a distance equal to -----
f1+f2
f1-f2
f1/f2
f1+f2/2
8. If the effective indices of the material of the prism are nv = 1.6 and nr= 1.4, its dispersive power is ------
0.2
3
1
0.4
9. For achromatism the distance between two lenses of focal lengths 12 cm and18 cm must be equal to ------
15 cm
30 cm
6 cm
3 cm
10. A convex has mean focal length 20 cm The dispersive power of the material of the lens is 0.02. The longitudinal chromatic aberration for an object at infinity is ------
0.40
0.20
0.80
1.0
