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. Human have also used natural observations to design their

special purpose “fast moving objects” like the racing cars. Such objects are given special shapes.

(a) Identify contact and non-contact force from the following given forces (1x4=4)

(i)

Gravitational force

(ii)

Frictional force

(b) “Gravitational force is a non-contact force”. Justify the statement.

(c) Why are objects given special shapes when they are moving through fluids?

(d) Write the name given to these special shapes?

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Answer 1

Explanation:

before is black after is white