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Multiple choice physics fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

Hydraulic press works on the principle of Pascal's principle

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pascal law states that any increment in pressure applied to the enclosed fluid is transmitted undiminished at each pt of the fluid and the walls of the container.

and  hydraulic press works on the principle of pascal law 
so option (A) is correct.

Multiple choice physics fluid pressure examples of hydraulic press applications of pascal's law pascal's law and its applications

Lifting automobiles in service stations is based on the principle of ________.

  1. Apparent pressure 

  2. <span>Hydraulic pressure</span>

  3. Atmospheric pressure

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lifting automobiles in service stations is based on the principle of Hydraulic pressure .

hydraulic press is based on the pascal law .
so option (B) is correct

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

The radii of the press plunger and the pump plunger are in the ratio 30 : 4. If an effort of 32 kgf acts on the pump plunger. Find the maximum effort the press plunger can overcome.

  1. <span>1600 kgf</span>

  2. <span>1700 kgf</span>

  3. <span>1800 kgf</span>

  4. <span>1900 kgf</span>
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

$\dfrac {\text {Radius of the press plunger}}{\text {Radius of pump plunger}}=\dfrac {R}{r}$


$=\dfrac {30}{4}$

According to the principal of hydraulic machine,

$\dfrac {L}{E}=\dfrac {\pi R^2}{\pi r^2}$

$\Rightarrow \dfrac {L}{32 kgf}=(\dfrac {30}{4})^2$


$\Rightarrow \dfrac {L}{32}=\dfrac {900}{16}$

$\Rightarrow L=\dfrac {900\times 32}{16}=1800 kgf$

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

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 

  1. $71.4 \mathrm { kg }$

  2. $68.6 \mathrm { kg }$

  3. $70.0 \mathrm { kg }$

  4. $84.0 \mathrm { kg }$
Reveal answer Fill a bubble to check yourself
B Correct answer
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.

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

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-

  1. $h\rho gA$

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

  3. $2h\rho gA$

  4. $\cfrac{1}{4}h\rho g A$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The velocity of efflux is v = sqrt(2gh). The force of reaction is F = dm/dt * v = (rho * A * v) * v = rho * A * v^2. Since there are two holes, the total force is 2 * rho * A * (2gh) = 4 * rho * A * g * h. Given the specific geometry, the standard result for this problem is 2 * rho * A * g * h.

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

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

  1. they look good

  2. they amplify the force applied by a large extent

  3. they are sturdy

  4. they have better tensile strength
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hydraulic lifts works on the pascals law principle 

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