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tatement: For the streamline flow of non-viscous and incompressible liquid, the sum of potential energy, kinetic energy and pressure energy is constant.

Proof:

Let us consider the ideal liquid of density ρ flowing through the pipe LM of varying cross-section.

Let P₁ and P₂ be the pressures at ends L and M and A₁ and A₂ be the areas of cross-sections at ends L and M respectively.

Let the liquid enter with velocity V₁ and leave with velocity v₂.

Let A₁ > A₂.

Now, by equation of continuity,

Since, A₁ > A₂

Therefore,

v₂ > v₁ and P₁> P₂

Let, m be the mass of liquid enetring at end L in time t.

The liquid will cover a distance = v₁t

Therefore, the work done by pressure on the liquid at end L in time t is,

W₁ = Force

= P₁A₁v₁t ... (1)

Since same mass m leaves the pipe at end M in same time t, in which liquid will cover the distance given by v₂t.

Therefore, work done by liquid against the force due to pressure P₁ is given by,

W₂ = P₂A₂v₂t ... (2)

Net ork done by pressure on the liquid in time t is,

W = W₁ - W₂

=P₁A₁v₁t - P₂A₂v₂t ... (3)

This work done on liquid by pressure increases it's kinetic energy and potential energy.

Increase in K.E of liquid is,

That is,

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ANSWER

Derivation of cp-cv=R

Posted by Alok Kumar 7 years, 1 month ago

CBSE > Class 11 > Physics

1 answers

Gaurav Seth 7 years, 1 month ago

Consider one mole of an ideal gas enclosed in a cylinder fitted with the movable frictionless piston.

Let the gas be heated at constant volume.

On supplying dQ amount of heat, let the temperature of the gas increase by dT.

By first law of thermodynamics,

dQ = dU + dW = dU + PdV

C_pdT = C_vx dT + RdT

At a constant pressure,

P.dV = R.dT

where C_p_,C_vand R are in same units.

Hence, proved.

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I. Dont understnnd physics

Posted by Ashad Khan 7 years, 1 month ago

CBSE > Class 11 > Physics

0 answers

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I have exams in 2 days and haven't even covered any single chapter.. Is there any chance I can pass my exams ?

Posted by Kumari Jetawni 7 years, 1 month ago

CBSE > Class 11 > Physics

2 answers

Ashad Khan 7 years, 1 month ago

Just study it prolerly

1Thank You

Riya Chouhan 7 years, 1 month ago

Yes u can pass by starting preparation nowonwards and by reading cbse revision notes.

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Why do air bubbles in a liquid move in an upward direction?

Posted by Kalpana Thejkumar 7 years, 1 month ago

CBSE > Class 11 > Physics

3 answers

Appy Garnara 7 years, 1 month ago

Because the density of the bubbles are lighter than the liquid

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Gaurav Seth 7 years, 1 month ago

Because the pressure inside the air bubble is greater than the atmoshpheric pressure.So they move upwards.

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Vinayak Gupta 7 years, 1 month ago

I think because of their light weight

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||gm law of vector addition

Posted by Manu Thakur 7 years, 1 month ago

CBSE > Class 11 > Physics

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Posted by Kaira Choudhary 7 years, 1 month ago

CBSE > Class 11 > Physics

2 answers

Shayok Mukherjee 7 years, 1 month ago

Its the apparent change in the frequency as observed by the observer due to the relative velocities of the source and the observer.

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Mann Patidar 7 years, 1 month ago

The Doppler effect is defined as a noticeable change in the frequency of sound, light or water waves as the source and the observer move.

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Avogadros hypothesis for measuring radius of the atom

Posted by Manu Thakur 7 years, 1 month ago

CBSE > Class 11 > Physics

0 answers

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Ncert example no. 8.2

Posted by Gaurav Varma 7 years, 1 month ago

CBSE > Class 11 > Physics

1 answers

Gaurav Varma 7 years, 1 month ago

2Thank You

ANSWER

What is Bernoulli s theorem

Posted by Shivam Kumar 7 years, 1 month ago

CBSE > Class 11 > Physics

2 answers

Balraj Singh 7 years, 1 month ago

The sum of pressure energy kinetic energy potential enrgy per unit vilume of a non viscous incompressible fluid and its streamlined and irrational flow become Constan

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Sangeeth M?? 5 years, 11 months ago

Pressure + 1/2*density*velocity^2 +density*acc due to gravity*height=constant

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Obtain an expansion for pressure of a liquid coloumn

Posted by Ahmed Hussain 7 years, 1 month ago

CBSE > Class 11 > Physics