Question

answer the question ​

Answer 1

1. It is difficult to hold a school bag having a thin strap because since the contact surface area on the shoulder is very small, the pressure exerted on the shoulder is very large.

2. The phenomenon in which the upward force exerted by fluids on objects when they are immersed in them is called buoyancy.

3.  If the density of an object is more than the density of the liquid, then it sinks in the liquid. This is because the buoyant force acting on the object is less than the weight of the object.

If the density of the object is less than or equal to the density of the liquid, then it floats on the surface of the liquid. This is because the buoyant force acting on the object is equal to the weight of the object.

Answer 2

1. A strap made of a thin and strong string has less area which results in increase in pressure. So, it is difficult to hold a school bag having a strap made of a thin and strong string.
2. The upward force exerted by fluids on an object is known as upthrust or buoyancy. The object may be partially or fully immersed in fluid.
3. It is because of the density of the object . The density of a substance is defined as the mass per unit volume. Objects of density less than that of a liquid float on the liquid. While, the objects of density greater than that of a liquid sink in the liquid.