In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c ) If assertion is true but reason is false.
(d) If assertion and reason are false.
Q. A needle placed carefully on the surface of water may float, whereas a ball of the same material will always sink.
Reason: The buoyancy of an object depends both on the material and shape of the object.

Answer

C

Explanation

Needle floats due to surface tension there is no role of buoyant force in its floating.
Buoyant force `=Vsigmag`
where `V=` volume of body submerged in liquid
`sigma=`density of liquid.
i.e., the buoyancy of an object depends on the shape of the object.