Tag: when do objects float on water?

Questions Related to when do objects float on water?

A solid floats in a liquid in the partially submerged position:

physics upthrust in fluids, archimedes' principle and floatation applications of floatation principle of floatation and its applications when do objects float on water?

  1. the solid exerts a force equal to its weight on the liquid

  2. the liquid exerts a force of buoyancy on the solid which is equal to the weight of the solid

  3. the weight of the displaced liquid equals the weight of the solid

  4. all of the above

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Correct Option: D
Explanation:

Given that solid floats in a liquid, in the partially submerged position.

The weight of the displaced liquid will be equal to the weight of the solid, and the solid exerts a force equal to the weight of the liquid.
The weight of solid is equal to the buoyancy force exerted by the liquid on the solid.
Therefore option $D$ is correct.

In a beaker containing liquid, an ice cube is floating. When ice melts completely, the level of liquid rises. Then the density of the liquid is:

physics upthrust in fluids, archimedes' principle and floatation applications of floatation principle of floatation and its applications when do objects float on water?

  1. more than the density of ice

  2. less than the density of ice

  3. same as the density of ice

  4. none of the above

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Correct Option: A
Explanation:

Given, That the ice cube is floating in the liquid.

Let the height of ice cube be $h,$
Given, If ice cube completely melts, the level of liquid raises. So initially the length of ice cube submerged in liquid be $l <h,$
Let the density of liquid be $d _{l}$ and density of ice cube be $d _{i}$
In equilibrium , $Mg=M _{l}g$
$\Rightarrow d _{i}Ahg=d _{l}Alg$
$\Rightarrow \frac{d _{l}}{d _{i}}=\frac{h}{l}>1$
$\Rightarrow d _{l} > d _{i}$
Therefore the density of liquid is more than the density of ice.
So option $A$ is correct.

An ice cube contains a large air bubble. The cube is floating on the surface of water contained on a trough. What will happen to the water level, when the cube melts?

physics upthrust in fluids, archimedes' principle and floatation applications of floatation principle of floatation and its applications when do objects float on water?

  1. $It\ will\ remain\ unchanged$

  2. $It\ will\ fall$

  3. $It\ will\ rise$

  4. $First\ it\ will\ and\ then\ rise$

Show answer
Correct Option: B
Explanation:

Since density of a hollow ice cube is less than water. Hence it will float and when ice melts, then level of water decreases due to loss in volume.