Fluid Mechanics

The statement claims 'The density of water is 1.0 grams.' Density is defined as mass per unit volume and requires units like g/cm³ or g/mL. While water's density is approximately 1.0 g/cm³ at 4°C, stating it as '1.0 grams' is dimensionally incorrect - grams measure mass, not density. The correct answer is False because density cannot be expressed in grams alone.

Pressure in a fluid depends only on depth, not on the width or volume of the container. Both the lake and the well are 10 meters deep, so the pressure at the bottom is identical (P = ρgh, where h is depth). The large width of the lake doesn't increase pressure.

Objects that sink still experience buoyant force equal to the weight of the displaced water (Archimedes' principle). They sink because their weight is greater than the buoyant force, not because buoyancy is absent.

Water seeks its own level due to water pressure increasing with depth (P = rho * g * h). In connected vessels, water flows until pressures at the same horizontal level equalize, which occurs when water surfaces are at the same height. Atmospheric pressure is the same on all surfaces and cancels out, while density and 'g' don't determine level-seeking behavior.

When iron is in the boat, it displaces water equal to its weight. When submerged, it displaces water equal to its volume. Since iron is denser than water, its volume is less than the volume of water with the same weight, so less water is displaced overall.

The fraction of an ice cube submerged depends only on the density ratio of ice to liquid, not on gravitational acceleration. This ratio is unchanged on the moon, so the submerged volume remains 9/10.

A siphon works due to gravitational pressure difference, with liquid flowing from the higher vessel to the lower one. If both liquid levels are at the same height, there's no pressure difference to drive the flow. Equal density, unequal limb length, or equal temperature don't prevent siphon action - it's the equal height that eliminates the driving force.

Surface tension is the cohesive force at a liquid's surface that minimizes surface area, causing droplets to assume spherical shape (the shape with minimum surface area for a given volume). Viscosity relates to fluid thickness, density to mass per volume.

A siphon operates due to the pressure difference created by a height difference between liquid levels. When both vessels have liquid at the same level, there's no gravitational pressure gradient to drive flow, causing the siphon to fail regardless of tube configuration.

Surface tension is the cohesive force that causes liquid droplets to minimize their surface area by assuming a spherical shape. Among the options, surface tension is the correct physical phenomenon responsible for this behavior. Viscosity relates to fluid flow resistance, density to mass per volume, and kinematic viscosity to viscosity divided by density.

Surface tension of water is a contractive tendency of the surface of a liquid that allows it to resist an external force. It is revealed, for example, in the floating of some objects on the surface of water, even though they are denser than water, and in the ability of some insects (e.g water striders to run on the water surface. This property is caused by cohesion of similar molecules and is responsible for many of the behaviors of liquids..

The surface tension of liquid is responsible for that ,the tension at surfaces of a drop acts inwards to the center so drop tends to reduced its volume and the minimum possible volume for matter is a sphere and therefore a falling drop of liquid acquires the spherical shape.

A lead ball falls through water more slowly than through air because of the viscous force in water.

Speed of sound in normal air is 343 m/s. In water, the speed is 1433 m/s. Speed of sound in metals is even more; like in copper, it is 4600 m/s and in iron, it’s 5130 m/s.