Radio waves coming at `angle_alpha` to vetical are received by a radar after reflection from a nearby water surface and directly .what should be height of antenna from water surface so that it records a maximum intensity.(Wavelength =`lambda`)

The wave reaching the receiving antenna will have maximum intensity if the direct wave & wave after reflection from earth's surface

A sound wave having wavelength lambda forms stationary waves after reflection from a surface. The distance between two consecutive nodes is

The formula for value of horizontal velocity of water coming from hole at the bottom at a height h from the surface of water is ……

Water is filled to a height in a long container. From what height below the free surface a hole should be bored in the wall of a container so that the horizontal range is maximum?

The light reflected from water surface (mu = 1.3) is completely polarised. The angle of incidence will be

A person standing at a distance of 6 m from a source of sound receives sound wave in two ways, one directly from the source and other after reflection from a rigid boundary as shown in figure. The maximum wavelength for which, the person will receive maximum sound intensity, is

A person standing at a distance of 6 m from a source of sound receives sound wave in two ways, one directly from the source and other after reflection from a rigid boundary as shown in the figure. The maximum wavelength for which, the person will receive maximum sound intensity, is