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

Answer:

♦A force is a push or pull upon an object resulting from the object's interaction with another object. Whenever there is an interaction between two objects, there is a force upon each of the objects. When the interaction ceases, the two objects no longer experience the force.

♦Two bodies interacting

Pairs of objects interact, by collision or explosion. As there is only one interaction, the contact time is the same for both objects. That's the duration for which the force exerted by one acts on the other. ... The actions of the forces are opposite in direction but equal in magnitude.

♦Contact forces are forces that act between two objects that are physically touching each other.

Answer 2

Answer:

muscular and frictional force

because they attract each other but they don't contact