CBSE
Multiple Choice QuestionsThe intensity ratio of the maxima and minima in an interference pattern produced by two coherent sources of light is 9 : 1. The intensities of the used light sources are in ratio
3 : 1
4 : 1
9 : 1
10 : 1
Assertion: Two point coherent sources of light S1 and S2 are placed on a line as shown. P and Q are two points on that line. If at point P maximum intensity is observed then maximum intensity should also be observed at Q.
Reason: In the figure of assertion the distance is equal to distance .
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
In a Fraunhofer diffraction at single slit of width d with incident light of wavelength 5500 Ao, the first minimum is observed, at angle 30°. The first secondary maximum is observed at an angle θ =
sin-1
sin-1
sin-1
sin-1
Assertion: In YDSE bright and dark fringe are equally spaced.
Reason: It only depends upon phase difference.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
In a certain double slit experimental arrangement, interference fringes of width 1 mm each are observed when light of wavelength 5000 Ao is used. Keeping the setup unaltered, if the source is replaced by another of wavelength 6000 Ao, the fringe width will be
1.2 mm
0.5 mm
1 mm
1.5 mm
Assertion: A ray of light is incident from outside on a glass sphere surrounded by air. This ray may suffer total internal reflection at second interface.
Reason: If a ray of light goes from denser to rarer medium, it bends away from the normal.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Two slits are separated by a distance of 0.5 mm and illuminated with light of wavelength λ = 6000 Ao. If the screen is placed at 2.5 m from the slits. The distance of the third bright fringe from the centre will be
1.5 mm
3 mm
6 mm
9 mm
The two coherent sources with intensity ratio β produce interference. The fringe visibility will be
2 β
Assertion: In a common emitter transistor amplifier, the input current is much less than the output current than output impedance.
Reason: The common emitter transistor amplifier has higher input impedance than output impedance.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
The magnification produced by a astronomical telescope for normal adjustment is 10 and the length of the telescope is 1.1 m. The magnification, when the image is formed atleast distance of distinct vision is
6
18
16
14
