A coin placed at the bottom of a tank appears to be raised,when water is poured into the tank.Why?

Why are f-block elements placed at the bottom of the periodic table ? Give the names of the series present in the block.

An explosion takes place at the bottom of a lake.What type of waves are produced inside the water?

A small bulb is placed at the bottom of a tank containing water to a depth of 80cm. What is the area of the surface of water through which light from the bulb can emerge out? Refractive index of water is 1.33. (Consider the bulb to be a point source.)

A concve mirror of radius of curvature 1 m is placed at the bottom of a tank of water.The mirror forms an image of the sun,when it is directly overhead.Calculate the distance of the images from the mirror for different depths,80 cm and 40 cm of the water in the tank.

A mark is made at the bottom of a beaker and a microscope is focussed on it.the microscope is then raised through 0.015 m.To what height water must be poured into the beaker to bring the mark again into focus?Given a^mu_w = 4//3 .

In filling the gasoline tank of an aeroplane, the metal nozzle of the hose from the gasoline truck is always carefully connected to the metal of the aeroplane by a wire, efore the nozzle is inserted in the tank . Explain why.

The water for a factory is stored in a hemispherical tank whose internal diameter is 14 m. The tank contains 50 kilo litres of water. Water is pumped into the tank to fill to its capacity. Calculate the volume of water pumped into the tank.

Water comes out of a cell when it is placed in: