Mechanical Prop...

A concrete sphere of radius R has a cavity of radius r which is packed with sawdust. The specific gravities of concrete and sawdust are respectively 2.4 and 0.3 for this sphere to float with its entire volume submerged under water. Ratio of mass of concrete to mass of sawdust will he

A tank 5 m high is half filled with water and then is filled to the top with oil of density 0.85 g/cm³. The pressure at the bottom of the tank, due to these liquids is

A wooden block of volume 1000 cm³ is suspended from a spring balance. It weighs 12 N in air. It is suspended in water such that, half of the block is below the surface of water. The reading of the spring balance is

A capillary tube is attached horizontally to a constant head arrangement. If the radius of the capillary tube is increased by 10%, then the rate of flow of liquid will change nearly by

A soap film of surface tension 3 × 10^–2Nm^–1 formed in rectangular frame, can support a straw. The length of the film is 10 cm. Mass of the straw the film can support is

If the work done in blowing a bubble of volume V is W, then the work done in blowing the bubble of volume 2V from the same soap solution will be

The value of surface tension of a liquid at critical temperature is

The spherical shape of rain-drop is due to

When there is no external force, the shape of a liquid drop is determined by