To what height should water be filled in a 21 cm high vessel so that the vessel appears half full when viewed from above? ,

How much water should be filled in a container 21 cm in height, so that it appaers half filled when viewed from the top of the contaier? [Given that : _(a) mu _(w) = (4)/(3) ]

How much water should be filled in a container of height 21 cm, so that it appears half filled to the observer when viewed from the top of the container (mu=4//3).

How much water (in cm) should be filled in a container of height 12 cm, so that it appears half filled to the observer when viewed from the top of the container (mu=4//3) .

Water level is maintained ina cylindrical vessel up to a fixed height H. The vessel is kept on a horizontal plane. At what height above the bottom should a hole be made in the vessel so that the water stream coming out of the hole strikes the horizontal plane at the greatest distance from the vessel.

A vessel contains water up to a height of 20 cm and above it an oil up to another 20 cm. The refractive indices of the water and the oil are 1.33 and F30 respectively. Find the apparent depth of the vessel when viewed from above.