Advertisements
Advertisements
प्रश्न
If the light moving in a straight line bends by a small but fixed angle, it may be a case of
(a) reflection
(b) refraction
(c) diffraction
(d) dispersion.
उत्तर
(a) reflection
(b) refraction
When the light strikes on a surface nearly parallel to it, it then bends by a small and fixed angle after reflection. Also, when the light travels from one medium to another with slight differences in their refractive indices, it bends by a small angle. Thus, the bending of light by a small but fixed angle can be the case of either reflection or refraction.
APPEARS IN
संबंधित प्रश्न
A tank is filled with water to a height of 12.5 cm. The apparent depth of a needle lying at the bottom of the tank is measured by a microscope to be 9.4 cm. What is the refractive index of water? If water is replaced by a liquid of refractive index 1.63 up to the same height, by what distance would the microscope have to be moved to focus on the needle again?
Double-convex lenses are to be manufactured from a glass of refractive index 1.55, with both faces of the same radius of curvature. What is the radius of curvature required if the focal length is to be 20 cm?
A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is?
Does the apparent depth of a tank of water change if viewed obliquely? If so, does the apparent depth increase or decrease?
Light incident normally on a plane mirror attached to a galvanometer coil retraces backward as shown in Figure. A current in the coil produces a deflection of 3.5° of the mirror. What is the displacement of the reflected spot of light on a screen placed 1.5 m away?
A converging lens has a focal length of 20 cm in air. It is made of a material of refractive index 1·6. If it is immersed in a liquid of refractive index 1·3, find its new focal length.
For the same value of angle of incidence, the angles of refraction in three media A, B and C are 15°, 25° and 35° respectively. In which medium would the velocity of light be minimum?
A narrow beam of light passes through a slab obliquely and is then received by an eye following figure. The index of refraction of the material in the slab fluctuates slowly with time. How will it appear to the eye? The twinkling of stars has a similar explanation.
An object P is focussed by a microscope M. A glass slab of thickness 2.1 cm is introduced between P and M. If the refractive index of the slab is 1.5, by what distance should the microscope be shifted to focus the object again?
Stars twinkle due to ______.
A ray of light travelling in a transparent medium of refractive index n falls, on a surface separating the medium from air at an angle of incidents of 45°. The ray can undergo total internal reflection for the following n.
What is optical path? Obtain the equation for optical path of a medium of thickness d and refractive index n.
Obtain the equation for apparent depth.
Obtain the equation for critical angle.
A light travels through water in the beaker. The height of water column is 'h'. Refractive index of water is 'μw'. If c is velocity of light in air, the time taken by light to travel through water will ______.
The critical angle for a ray of light from glass to air is 'θ' and refractive index of glass with respect to air is 'n'. If a ray of light is incident from air to glass at an angle 'θ', then corresponding angle of refraction is ______.
The critical angle is maximum when light travels from ______.
`(a^mu"w"=4/3,a^mug=3/2)`
A convex lens made of material of refractive index 1.5 and having a focal length of 10 cm is immersed in a liquid of refractive index 3.0. The lens will behave as ______.
