Question

1.Why does a buffalo float on the river but not the man?

Answer 1

a buffalo floats on water whereas a man does not.this is because the buffalo has more surface area . so the force exerted by it gets distributed over a large area and pressure is reduced.whereas a man does not float because he has a smaller surface area and pressure exerted is increased
(note:man can float on water if he is in a horizontal position .this way he covers more surface area and pressure exerted is reduced)

Answer 2

surface area of abuffalo is more than that of a man. so pressure applied by buffalo is less than by aman.pressure is force acting /unit area.so man cant float on the river