Question

We know that forces arise due to some mutual interaction between two

entities and their interaction effects can come into play through a “direct

contact” or even without a "direct contact". A special type of a “direct

contact” force has the general effect of slowing down moving objects. Nature

has taken special care to minimize the slowing down effect of this force

on birds and fishes who have to move through fluids a lot. Humans have

also used natural observations to design their special purpose “fast moving

objects” like the racing cars. Such objects are given special shapes.

(a) Give any two examples of 'contact force'.

(b) "Magnetic force is a non-contact force". Justify the statement.

(c) How has nature tried to minimize the slowing effect of the special

force that tends to slow down birds when they move through air or

fish when they move through water?

(d) Will one really need special vehicles if they were to race through

vaccum or free space?​

Answer 1

a) Muscular Force, Gravitational Force

b) A magnet need not to be in contact with the object. When an object kept over sand iron fillings attach to them. This shows that magnets need not be in contact with force.

c) Nature slows down the air and speed of the fish in the stream with water

d) Yes, they will have to need because in the place where there is gravity we can go at any speed. But in space due to no gravity we need special vehicles.