Question

The contact force exerted by a body a on another body b is equal to the normal force between the bodies. we conclude that -

Answer 1

Hey

(a) the surfaces must be friction-less

(b) the force of friction between the bodies is zero

(c) the magnitude of normal force equals that of friction

(d) the bodies may be rough but they don't slip on each other.
I think these are the options of the Question.

So now,
we can conclude that (b) & (d) are the right options because of the following reason:

(b) Contact Force F will be equal to Normal Force Fn only if the Frictional force f is zero.
Therefore, (b) is correct.

(d) If the bodies may be rough but they don't slip on each other then the Frictional force f is zero also the Normal force is equal to the Contact force.
Therefore, (d) is correct.


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