Question

Give scientific reasons;

(1) The ships entering fresh water from sea water sink to a greater extent.

(2) The cutting edges of tools like knives, blades etc are provided with sharp edges.

Answer 1

_{(1) As we know that the density of fresh water is less than that of sea water, the buoyant force on the ship in fresh water is less than that of sea water. Due to this reason, the ships entering the fresh water from the sea water sink to a greater extent.}

_{(2) We know,}

_{We see pressure is inversely proportional to the area. This concept is used in cutting anything with knives and blades. We apply force on knives and blades to cut anything. If the area is smaller we need to apply little force to complete the task. Since the sharp edge of knives and blades have a smaller area, we need to apply little force. Due to this reason, the cutting edges of tools like knives and blades are provided with sharp edges.}