Statement I: A needle placed carefully on the surface of water may float, whereas the ball of the same material will always sink.
Statement II: The buoyancy of an object depends both on the material and shape of the object.

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.

Assertion: A needle placed carefully on the surface of water may float. Reason: A needle placed carefully on the surface of water may float due to the surface tension as upward forces due to surface tension balances the weight of the needle.

Whi does an object float or sink when placed on the surface of water?

Statement I : Escape velocity of a tennis ball from the surface of earth is the same as the escape velocity of a cricket ball from the surface of earth. Statement II : Escape velocity of a body is independent of the mass of the body

Statement I: An object from a greater height reaches a steady terminal velocity. Statement II: The viscous forces on a body depends upon its velocity. The greater the velocity the greater is the viscous force.

Statement-1: Leaves and small insects float on the surface of water buoyed up by archimede's principle Statement-2: They are not partially submerged. The object are kept afloat by surface tension.

Statement I: Droplets of liquid are usually more spherical in shape than large drops of the same liquid. Statement II: Force of surface tension predominates force of gravity in case of small drops.

Statement-1: A thin stainless steel needle can lay floating on a still water surface. Statement-2: Any object floats when the buoyancy force balances the weight of the object.

Statement I : Convex mirror is used as a rear view mirror. Statement II: Convex mirror always forms virtual, erect and diminished image for all positions of the object.