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Radio waves coming at angle a to vertical are received by a ladder after reflection from a nearby water surface and also directly. What can be height of antenna from water surface so that it records a maximum intensity (a maxima) (wavelength = l )
The correct answer is:
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Two coherent narrow slits emitting wave length l in the same phase are placed parallel to each other at a small separation of 2 l , the sound is detected by moving a detector on the screen S at a distance D (>> l ) from the slit S1 as shown in figure.Find the distance x such that the intensity at P is equal to the intensity at O
Two coherent narrow slits emitting wave length l in the same phase are placed parallel to each other at a small separation of 2 l , the sound is detected by moving a detector on the screen S at a distance D (>> l ) from the slit S1 as shown in figure.Find the distance x such that the intensity at P is equal to the intensity at O
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Sound from two coherent sources S1 and S2 are sent in phase and detected at point P equidistant from both the sources. Speed of sound in normal air is V0 , but in some part in path S1 , there is a zone of hot air having temperature 4 times, the normal temperature, and width d. What should be minimum frequency of sound, so that minima can be found at P?
Sound from two coherent sources S1 and S2 are sent in phase and detected at point P equidistant from both the sources. Speed of sound in normal air is V0 , but in some part in path S1 , there is a zone of hot air having temperature 4 times, the normal temperature, and width d. What should be minimum frequency of sound, so that minima can be found at P?
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Figure shows two snapshots of medium particles within a time interval of 1/60 s. Find the possible time periods of the wave
Figure shows two snapshots of medium particles within a time interval of 1/60 s. Find the possible time periods of the wave
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Two coherent sources S1 and S2 at a distance interference effect at point P,O is the middle point of S1S2 and origin of the coordinate system, as shown, such that 
Find the coordinate of source S1 when sources are rotated about point O so that no interference effect is observed at P:
Two coherent sources S1 and S2 at a distance interference effect at point P,O is the middle point of S1S2 and origin of the coordinate system, as shown, such that Find the coordinate of source S1 when sources are rotated about point O so that no interference effect is observed at P:
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A boy is moving along a circular track in anticlockwise sense. A children train moves along a square path with centres of circular track and square both coinciding, as shown in the figure. the train as well as the boy start from points B and A such that points O, A and B always lie on the same radial line. The velocity of listener is 11 m/s. The train continuously whistles at frequency 300 Hz. during one such complete rotation the maximum and minimum frequency heard by the boy. are respectively ( Take velocity of sound 330 m/s)
A boy is moving along a circular track in anticlockwise sense. A children train moves along a square path with centres of circular track and square both coinciding, as shown in the figure. the train as well as the boy start from points B and A such that points O, A and B always lie on the same radial line. The velocity of listener is 11 m/s. The train continuously whistles at frequency 300 Hz. during one such complete rotation the maximum and minimum frequency heard by the boy. are respectively ( Take velocity of sound 330 m/s)
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The figure shows the location of a source and detector at time t = 0. the source and detector are moving with velocities 
respectively. The frequency of signals received by the detector at the moment when the source crosses the origin is ( the frequency of source is 100 Hz.velocity of sound 330 ms -1)
The figure shows the location of a source and detector at time t = 0. the source and detector are moving with velocities respectively. The frequency of signals received by the detector at the moment when the source crosses the origin is ( the frequency of source is 100 Hz.velocity of sound 330 ms -1)
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A police car moving at 22 m/s chases a motorcyclist. The police man sound his horn at 176 Hz, while both of them move towards a stationary siren of frequency 165 Hz. If the motorcyclist does not observe any beats, the speed of motor cycle is 
A police car moving at 22 m/s chases a motorcyclist. The police man sound his horn at 176 Hz, while both of them move towards a stationary siren of frequency 165 Hz. If the motorcyclist does not observe any beats, the speed of motor cycle is
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A massless rod of length 
is hung from the ceiling with the help of two identical wires attached at its ends. A block is hung on the rod at a distance x from the left end. In this case, the frequency of the 1st harmonic of the wire on the left end is equal to the frequency of the 2nd harmonic of the wire on the right. The value of x is
A massless rod of length is hung from the ceiling with the help of two identical wires attached at its ends. A block is hung on the rod at a distance x from the left end. In this case, the frequency of the 1st harmonic of the wire on the left end is equal to the frequency of the 2nd harmonic of the wire on the right. The value of x is
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An incandescent light bulb has a tungsten filament that is heated to a temperature 
when an electric current passes through it. If the surface area of the filament is approximately 
and it has an emissivity of 0.32, the power radiated by the bulb is
An incandescent light bulb has a tungsten filament that is heated to a temperature when an electric current passes through it. If the surface area of the filament is approximately and it has an emissivity of 0.32, the power radiated by the bulb is
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One end of a cylindrical rod is kept in steam chamber and the other end in melting Ice. Now 0.5 gm of ice melts in 1 sec. If the rod is replaced by another rod of same length, half the diameter and double the conductivity of the first rod, then rate of melting of ice will be
One end of a cylindrical rod is kept in steam chamber and the other end in melting Ice. Now 0.5 gm of ice melts in 1 sec. If the rod is replaced by another rod of same length, half the diameter and double the conductivity of the first rod, then rate of melting of ice will be
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A compound microscope has an objective lens of 1 cm and eyepiece of 2.5 cm focal length. When the object is placed at 1.1 cm from the objective, the final image is at the least distance of distant vision, the magnification produced and length of microscope is (nearly)
A compound microscope has an objective lens of 1 cm and eyepiece of 2.5 cm focal length. When the object is placed at 1.1 cm from the objective, the final image is at the least distance of distant vision, the magnification produced and length of microscope is (nearly)
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The effective focal length of the lens combination shown in figure is -60 cm. The radii of curvature of the curved surfaces of the plano-convex lenses are 12 cm each and refractive index of the material of the lens is 1.5. The refractive index of the liquid is
The effective focal length of the lens combination shown in figure is -60 cm. The radii of curvature of the curved surfaces of the plano-convex lenses are 12 cm each and refractive index of the material of the lens is 1.5. The refractive index of the liquid is
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A prism of glass 
is dipped in to water as shown in the figure. If the refractive index of water is 4/3, then the incident ray will be totally reflected if
A prism of glass is dipped in to water as shown in the figure. If the refractive index of water is 4/3, then the incident ray will be totally reflected if
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A layer of oil 3 cm thick is floating on a layer of coloured water 5 cm thick. The refractive index of the coloured water is 5/3 and the apparent depth of the two liquids is 
. Then the refractive index of theoil is,
A layer of oil 3 cm thick is floating on a layer of coloured water 5 cm thick. The refractive index of the coloured water is 5/3 and the apparent depth of the two liquids is . Then the refractive index of theoil is,
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Four lenses A, B, C and D of power +100D,-50D,20D and 5D. Which lenses will you use to design a compound microscope for best magnification?
Four lenses A, B, C and D of power +100D,-50D,20D and 5D. Which lenses will you use to design a compound microscope for best magnification?
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