A steel blade placed gently on the surface of water floats on it. If the same blade is kept well inside the water, it sinks. Explain.

A iron needle slowly placed on the surface of water floats on it because

Scum floats on the surface of the water because

A steel blade floats on the surface of pure water. When detergent is added it sinks , why?

Statement I: A needle placed carefully on the surface of water may float, whereas the ball of the same material will always sink. Statement II: The buoyancy of an object depends both on the material and shape of the object.

When a greased iron needle is placed gently on the surface of water at rest, it floats on the surface of water. Why?

Animals/ organisms floating on the surface of water are

Ice seems to be denser than water but it floats over it. Explain.

A dry clean steel needle of diameter d and density rho when carefully placed on the surface of water remains floating . If T is the surface tension of water , then maximum value for the diameter d of the needle for enabling it to float will be

A boat carrying steel balls is floating on the surface of water in a tank. If the balls are thrown into the tank one by one, how will it affect the level of water ?

A point source of light is placed at a depth of h below the surface of water of refractive index mu . A floating opaque disc is placed on the surface of water so that light from the source is not visible from the surface. The minimum diameter of the disc is