Tag: examples of hydraulic press

Questions Related to examples of hydraulic press

Sand and sawdust can be separated by _________.

chemistry fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. gravity separation

  2. calcination

  3. magnetic separation

  4. none of these

Show answer
Correct Option: A
Explanation:

Sand and saw dust can be separated by gravity separation method. The process can be used for separating insoluble substances which are heavier than liquid by allowing them to settle down on their own due to gravity.

The method of concentration of the ore that makes use of difference in density between ore and impurities is called __________.

chemistry fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. levigation

  2. leaching

  3. magnetic separation

  4. liquation

Show answer
Correct Option: A
Explanation:

Levigation is based on the difference in densities of the metallic ore and gangue particles. Powdered ore is treated with a stream of running water when the lighter gangue particles are washed away and heavier ore particles are left behind.

Water is poured from a height of 10 m into an empty barrel at the rate of 1 litre per second. If the weight of the barrel is 10 kg, the weight indicated at time t = 60 s will be 

physics pressure in fluids and atmospheric pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. $71.4 \mathrm { kg }$

  2. $68.6 \mathrm { kg }$

  3. $70.0 \mathrm { kg }$

  4. $84.0 \mathrm { kg }$

Show answer
Correct Option: B
Explanation:

Time taken to reach $10m$ below $=\sqrt {\dfrac{{2 \times 10}}{{10}}}  = \sqrt 2 \,\sec $

$\therefore $ only $\left( {60 - \sqrt 2 } \right)\sec $ is effective for pouring of water
$\therefore $ total weight $=10lkg+\left( {60 - \sqrt 2 } \right)l \times \dfrac{{1\,kg}}{l}$
$=58.6kg+10kg$
$=68.6kg$
Hence,
option $(B)$ is correct answer.

The residual pressure of a vessel at ${27}^{o}C$ is $1\times{10}^{-11}N/{m}^{2}$. The number of molecules per cc in this vessel is nearly

physics pressure in fluids and atmospheric pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. $2400$

  2. $2.4\times{!0}^{8}$

  3. ${10}^{-11}\times 6\times{10}^{23}$

  4. $2.68\times{10}^{-19}\times {10}^{-11}$

Show answer
Correct Option: C

Two identical holes of each of cross sectional area $A$ are opened on the opposite sides of a wide vertical vessel filled with water.The difference in vertical height of the two holes is $h$. The resultant force of reaction of water flowing out of vessel is-

physics pressure in fluids and atmospheric pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. $h\rho gA$

  2. $\cfrac{1}{2}h\rho g A$

  3. $2h\rho gA$

  4. $\cfrac{1}{4}h\rho g A$

Show answer
Correct Option: C

Write the correct alternatives :
In the Wilfley table method, the particles of gangue are separated by...................separation method.

chemistry fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. Magnetic

  2. Froth floatation

  3. Hydraulic

  4. Gravitational

Show answer
Correct Option: C
Explanation:

Hydraulic Washing :

In this method by flowing the powdered ore in a current of water, lighter rocky impurities can be washed away, for this, either wilfley table or Hydraulic classifier is used.

$\therefore$ option $"C"$ is correct.

Hydraulic lifts are used to lift the heavy loads primarily because :

physics pressure in fluids and atmospheric pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. they look good

  2. they amplify the force applied by a large extent

  3. they are sturdy

  4. they have better tensile strength

Show answer
Correct Option: B
Explanation:

Hydraulic lifts works on the pascals law principle 

therfore it amplify the force applied by a large extent  
hence option (B) is correct

Hydraulic washing is based on the differences in ___________ of the ore and gangue particles.

chemistry fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. specific gravities

  2. mass

  3. type of material

  4. none of these

Show answer
Correct Option: A
Explanation:

Hydraulic washing is a type of gravity separation, which is based on gravity differences between the ore and the gangue particles. In this process, the lighter gangue particles are washed away by a stream of water, leaving behind the heavier ore.

A large cylindrical tank has a hole of area $A$ at its bottom and water is poured into the tank through a tube of cross-section area $A$ ejecting water at the speed $v$. Which of the following is true?

physics pressure in fluids and atmospheric pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

  1. Water level in tank keeps on rising

  2. No water can be stored in the tank

  3. Water level will rise to height $v^{2}/2g$ and then stop

  4. The water level will be oscillating

Show answer
Correct Option: C
Explanation:

In the beginning ,the water escaping the vessel at the rate $\sqrt{2gh}$ and filling it at the rate of $vA$


So the rate of change in the water level of the vessel at any instant is 
($v-\sqrt{2gh})A$ 
where  'h' is the instantaneous height 

Since h is quite small in the beginning, the water is escaping the vessel at a slow rate but filling at a much larger rate as such    ($v-\sqrt{2gh})A$  ,is positive  (increase in water level)

soon after the filling of water  occurs, the height increases and the rate of escape become larger 
But when the rate =rate of filling ,then an equilibrium state is reached and there is no net change  in the height of the water 

the equilibrium is reached when ($v-\sqrt{2gh})A$ =0  $\rightarrow$  $h=\dfrac{v^2}{2g}$

State the principle on which a hydraulic press works. 

physics pressure in fluids and atmospheric pressure hydraulic equipment applications of pascals law examples of hydraulic press

  1. Archimedes principle

  2. Bernoulli's principle

  3. Pascals Law

  4. None of these

Show answer
Correct Option: C
Explanation:

It works on the principle of Pascals law.
Pascal's law: Pressure on a confined fluid is transmitted undiminished and acts with equal force on equal areas and at 90 degrees to the container wall.
Uses of hydraulic press - Hydraulic presses are commonly used for forging, clinching, moulding, blanking, punching, deep drawing, and metal forming operations.