Question

Two rods, a and b of the same weight and equal length, have different thicknesses. A boy, while playing with them on a beach, held them vertically on the surface of sand as shown in the figure . Which one of them will sink less? Explain.

Answer 1

Since, the two rods have the same weight the force exerted by them on the sand will be equal. But since they are of different thickness the rod will lesser thickness would generate more pressure and hence will sink more into the sand. The rod with greater thickness would generate lesser pressure and hence will sink less into the sand.