Exam 18: Ray Optics

In the figure,in the investigation of a new type of optical fiber (index of refraction n = 1.26),a laser beam is incident on the flat end of a straight fiber in air.What is the maximum angle of incidence θ₁ if the beam is not to escape from the fiber?

If a single lens forms a virtual image of an object,then

Light goes from medium A into medium B.If you measure that the angle the rays make with the normal in A is less than the angle they make with the normal in B,then you can conclude that the refractive index of A is less than the refractive index of B.

Situation 18.1 A tank holds a 1.44 m thick layer of oil that floats on a 0.96 m thick layer of brine.Both liquids are clear and do not intermix.Point O is at the bottom of the tank,on a vertical axis.The indices of refraction of the oil and the brine are 1.40 and 1.52,respectively. -In Situation 18.1,a ray originating at O reaches a point on the brine-oil interface at the critical angle.The distance of this point from the axis is closest to:

A concave spherical mirror has a focal length f.The image of an object located at a distance s > f in front of the mirror is real and inverted.

A ray in glass is incident onto a water-glass interface,at an angle of incidence equal to half the critical angle for that interface.The indices of refraction for water and the glass are 1.33 and 1.43,respectively.The angle that the refracted ray in the water makes with the normal is closest to:

A cylindrical tank is 50.0 ft deep,37.5 ft in diameter,and filled to the top with water.A flashlight shines into the tank from above.What minimum angle φ can its beam make with the water surface if the beam is to illuminate part of the bottom? (nwater = 1.33)

Light having a wavelength in vacuum of 600 nm enters a liquid of refractive index 2.0.In this liquid,its wavelength will be:

A glass plate whose index of refraction is 1.57 is immersed in a liquid.The surface of the glass is inclined at an angle of 54° with the vertical.A horizontal ray in the glass is incident on the interface.The liquid is an oil whose index of refraction is 1.40.The incident horizontal ray refracts at the interface.The angle that the refracted ray,in the oil,makes with the horizontal is closest to:

Which statement about thin lenses is correct? In each case,we are considering only a single lens.

Why shouldn't you spray water on your roses at noon?

Describe the operation of a one-way mirror.Is there actually such an optical element?

As you walk away from a plane mirror on a wall,your image

Light having a speed in vacuum of 3.0 × 10⁸ m/s enters a liquid of refractive index 2.0.In this liquid,its speed will be:

If an object is inside the focal point of a converging lens,this lens always produces a virtual image of that object;but if the object is outside the focal point,the lens always produces a real image.

Suppose you place your face in front of a concave mirror.

A fish appears to be 2.00 m below the surface of a pond when viewed almost directly above by a fisherman.What is the actual depth of the fish? (n_water = 1.33)

Situation 18.2 An erect object is 50 cm from a concave mirror of radius 60 cm. -In Situation 18.2,the object is moved to a new position,such that the new lateral magnification is +2.5.The new object distance,in cm,is closest to:

In old spy movies diamonds are hidden in a bottle of water or vodka.Would this really work?

A fisherman in a stream 39 cm deep looks downward into the water and sees a rock on the stream bed.How deep does the stream appear to the fisherman? Assume that the index of refraction of the water is 1.33.