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  • 1 answers

Yogita Ingle 4 years, 11 months ago

In rotation the body's centre of mass does not undergo any translation motion. In other words the centre of mass will remain at on place. Like a top spinning on its axis.

In circular motion the body's centre of mass goes around a fixed centre maintaining a constant distance from it. Which means the centre of mass is actually going through a translation motion. For example an ant sitting on the circumference of the spinning top in the above example.

The zeroth law of thermodynamics states that ‘two systems in thermal equilibrium with a third system separately are in thermal equilibrium with each other’. The Zeroth Law leads to the concept of temperature. 2. Internal energy of a system is the sum of kinetic energies and potential energies of the molecular constituents of the system. It does not include the over-all kinetic energy of the system. Heat and work are two modes of energy transfer to the system. Heat is the energy transfer arising due to temperature difference between the system and the surroundings. Work is energy transfer brought about by other means, such as moving the piston of a cylinder containing the gas, by raising or lowering some weight connected to it. 3. The first law of thermodynamics is the general law of conservation of energy applied to any system in which energy transfer from or to the surroundings (through heat and work) is taken into account. It states that ∆Q = ∆U + ∆W where ∆Q is the heat supplied to the system, ∆W is the work done by the system and ∆U is the change in internal energy of the system. Now suppose η R < ηI i.e. if R were to act as an engine it would give less work output than that of I i.e. W < W ′ for a given Q1 . With R acting like a refrigerator, this would mean Q2 = Q1 – W > Q1 – W ′. Thus, on the whole, the coupled I-R system extracts heat (Q1 – W) – (Q1 – W ′) = (W ′ – W ) from the cold reservoir and delivers the same amount of work in one cycle, without any change in the source or anywhere else. This is clearly against the Kelvin-Planck statement of the Second Law of Thermodynamics. Hence the assertion ηI > η R is wrong. No engine can have efficiency greater than that of the Carnot engine. A similar argument can be constructed to show that a reversible engine with one particular substance cannot be more efficient than the one using another substance. The maximum efficiency of a Carnot engine given by Eq. (12.32) is independent of the nature of the system performing the Carnot cycle of operations. Thus we are justified in using an ideal gas as a system in the calculation of efficiency η of a Carnot engine. The ideal gas has a simple equation of state, which allows us to readily calculate η, but the final result for η, [Eq. (12.32)], is true for any Carnot engine. This final remark shows that in a Carnot cycle, 2 1 2 1 T T = Q Q (12.33) is a universal relation independent of the nature of the system. Here Q1 and Q2 are respectively, the heat absorbed and released isothermally (from the hot and to the cold reservoirs) in a Carnot engine. Equation (12.33), can, therefore, be used as a relation to define a truly universal thermodynamic temperature scale that is independent of any particular properties of the system used in the Carnot cycle. Of course, for an ideal gas as a working substance, this universal temperature is the same as the ideal gas temperature introduced in section 12.11. I R W Fig. 12.12 An irreversible engine (I) coupled to a reversible refrigerator (R). If W ′ > W, this would amount to extraction of heat W′ – W from the sink and its full conversion to work, in contradiction with the Second Law of Thermodynamics. 2020-21
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  • 2 answers

Chitresh Khandal 4 years, 11 months ago

PA+qB+rC is this the answer

Kalki Kalki 4 years, 11 months ago

Open App  Salaam Rocky Bhai PLAY Chal ne ka hukum Ruk ne ka hukum Zindagi pe hukum Maut pe hukum Bandook pe hukum Dushman pe hukum Leharon pe hukum Bombai pe hukum Jaan Bambai ka, jaan Bambai ka Jaan Bambai ka jaane re Iski aankhon mein aankh na daalo Noch leta hai praan ve Aag toofan jab bhi milta hai Aisa barood paida hota hai Aye Khuda zara dekho Logon ke dil mein sultan dekho Dushman ko yeh hai shaitan dekho Aye Khuda zara roko Ruk ne wala karta Mud ne wala karta Bombai ki galiyan bhi Ghabra ke yun bolenge saala Salaam Rocky bhai Rock, Rock, Rocky Salaam Rocky bhai Salaam Rocky Bhai Salam Rocky bhai Ilaaka tera bhai Tu hai sabka bhai music........ Maa ne dua diya tum to panga liya jeetoge tum duniya khuda hairaan hoga maksad pura hoga ulta tairon dariyan kaun isko rokega kaha se layega fauj ko ek me bhi himmat bhi nahi hai panga lene ko jab bhi jaada hai haath loha hai jag ko bechain karne ka ye funda hai hat zara khatra hai apne wala karza murne wala karza mumbai ki galiyan bhi ghabra ke bolegi saala Salaam Rocky bhai Rock, Rock, Rocky Salaam Rocky bhai Salaam Rocky Bhai Salam Rocky bhai Ilaaka tera bhai Tu hai sabka bhai
  • 2 answers

Ashish Chauhan 4 years, 10 months ago

D=S×T D=90×-3 D=-270 m

Ashish Chauhan 4 years, 10 months ago

V= u+at O=90+30t t= -90/30 t = -3 s
  • 4 answers

Legendary 4 years, 11 months ago

?

Aadya Singh 4 years, 11 months ago

??

Dhruv ... 4 years, 11 months ago

??

Legendary 4 years, 11 months ago

Feastival
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  • 3 answers

Saloni Choudhary 4 years, 8 months ago

??

Saloni Choudhary 4 years, 11 months ago

Thanks

Yogita Ingle 4 years, 11 months ago

Scalar products can be found by taking the component of one vector in the direction of the other vector and multiplying it with the magnitude of the other vector”. It can be defined as: Scalar product or dot product is an algebraic operation that takes two equal-length sequences of numbers and returns a single number.

  • 2 answers

Abirami Kamalbabu 4 years, 10 months ago

The centre mass of the triangle always lies on the centroid of that triangle

Legendary 4 years, 11 months ago

It Lies on the centroid of triangle
  • 2 answers

Harish Thori 4 years, 11 months ago

M-1L3T-2

Yogita Ingle 4 years, 11 months ago

The dimensional formula of gravitational constant is given by,

M-1 LT-2

Where,

  • M = Mass
  • L = Length
  • T = Time
  • 1 answers

Yogita Ingle 4 years, 11 months ago

Given, mass, m = 72.2 kg
Gravity acceleration, g = 9.8 m/${{s}^{2}}$ Scale reading = apparent weight = R = ?
(i) While descending with constant velocity, a =0
R = mg
R = 72.2 x9.8
=>R = 707.56 N
(ii) While ascending with a = 3.2 m/${{s}^{2}}$
R = m(g + a)
R = 72.2 (9.8 + 3.2) = 938.6 N

  • 2 answers

Harish Thori 4 years, 11 months ago

Question to pura kro

Navi Phogat 4 years, 11 months ago

Pls, complete question first.
  • 1 answers

Gaurav Seth 4 years, 11 months ago

N = mg

 

Static friction provides the centripetal acceleration

 

fs =< μsN

 

mv2/r =< μsN

 

v2 =< μsNR/m = μsmgR/m = μsRg

 

v =< √ μsRg

 

This is the maximum speed of a car in circular motion on a level road

  • 2 answers

Anushka Sahu 4 years, 11 months ago

Hollow sphere is 2/3MR^2 And Solid sphere is 2/5MR^2

Yogita Ingle 4 years, 11 months ago

The moment of inertia of a sphere expression is obtained in two ways.

  • First, we take the solid sphere and slice it up into infinitesimally thin solid cylinders.
  • Then we have to sum the moments of exceedingly small thin disks in a given axis from left to right.

We will look and understand the derivation below.

First, we take the moment of inertia of a disc that is thin. It is given as;

I = ½ MR2

In this case, we write it as;

dI (infinitesimally moment of inertia element) = ½ r2dm

Find the dm and dv using;

dm = p dV

p = moment of a thin disk of mass dm

dv = expressing mass dm in terms of density and volume

dV = π r2 dx

Now we replace dV into dm. We get;

dm = p π r2 dx

And finally, we replace dm with dI.

dI = ½ p π r4 dx

The next step involves adding x to the equation. If we look at the diagram we see that r, R and x forms a triangle. Now we will use Pythagoras theorem which gives us;

r2 = R2 – x2

Now if we substitute the values we get;

dI = ½ p π (R2 – x2)2 dx

This leads to:

I = ½ p π -R(R2 – x2)2 dx

After integration and expanding we get;

I = ½ pπ 8/15 R5

Additionally, we have to find the density as well. For that we use;

p = m / V

p = m / m/v πR3

If we substitute all the values;

I = 8/15 [m / m/v πR] R5

I = ⅖ MR2

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Gaurav Seth 4 years, 11 months ago

 Let u & v be the velocity of the two trains named A & B.

While overtaking the relative velocity of train A with respect to B = u - v.

While crossing, the relative velocity of train A with respect to B = u + v.

Total distance to be travelled by Train A while crossing = 100 + 100 = 200.

So,

20 = 200 ÷ u-v

=> u - v = 10....1)

Also,

10 = 200 ÷ u + v

=> u + v = 20.......2)

On solving the equation 1 & 2, we get;

u = 15 M/S of the train A / First Train.

v= 5 M/S of the train B / Second Train.

  • 1 answers

Harish Thori 4 years, 11 months ago

Far
  • 2 answers

Legendary 4 years, 11 months ago

mai wshi hu brainly buddy meri identity kisi ko ptq nhi chalni chahiye ss ko bata dena wrna sb reveal ho jayega

? S.S.? 4 years, 11 months ago

AADYA...??????
  • 3 answers

Premchand Rajput 4 years, 11 months ago

List the main difference between mitosis and meiosis

Premchand Rajput 4 years, 11 months ago

1Q, summary of sweetest love I,Do Note Goe

Yogita Ingle 4 years, 11 months ago

Let 'u' be the initial velocity and 'a' the acceleration.
So we have the distance formula
s = ut + 1/2 at^2
In first 2 seconds,
s = 200
Put the values in the formula.
200 = u x 2 + 1/2 x a x (2)^2
200 = 2u + 1/2 x 4 x a
200 = 2u + 2a
100 = u + a -----(I)
In next 4 seconds
Let the distance traveled be 'y'
Time = 2+4 = 6 sec
So according to the formula ,
y = u x 6 + 1/2a x (6)^2
y = 6u + 1/2 x 36 x a
y = 6u + 18a ------(ii)
Now we know that 220 cm was traveled in between 2 sec - 6 sec
y - 200 = 220
y = 420
We know y = 6u + 18a (from [ii])
So, 6u + 18a = 420
u + 3a = 70 ------(iii)
Equating (I) and (iii)
-2a = 30
a = -15 cm/s^2
u = 100 - (-15)
u = 100 + 15 = 115 cm/sec
Now we know v = u + at
We have to find the "v" after 7th second
So v = 115 + (-15) x 7
v = 115 - 105
v = 10 cm/sec

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Abirami Kamalbabu 4 years, 10 months ago

Frequency =1 Angular velocity =2(3.14) R × frequency = 2(3.14)(0.5)(1) = 2(3.14) = 6.28 rad/s Linear velocity = angular velocity ×Radius = 6.28 (0.5) = 3.14 m/s
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Yogita Ingle 4 years, 11 months ago

Here, Mass of machine gun , M = 20 kg
mass of each bullet , m = 35 kg = 0.035 kg
velocity of bullet υ=400m/sυ=400m/s
Number of bullets/sec (n) =400/60=20/3 
Force required = rate of change of linear momentum of bullets =n(mυ)/t = 20/3  × 0.035×400/1 =93.3N 

  • 3 answers

Yogita Ingle 4 years, 11 months ago

Current density = Current​/area = Q/ area×t​ = [M0L−2T−1Q]

Jesika .. 4 years, 11 months ago

thanks yogita

Yogita Ingle 4 years, 11 months ago

The dimensional formula of current density is given by,

[M0 L-2 T0 I1]

Where,

  • M = Mass
  • I = Current
  • L = Length
  • T = Time
  • 2 answers

Gaurav Seth 4 years, 11 months ago

Statement: 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. By equation of continuity,


Yogita Ingle 4 years, 11 months ago

Bernoulli’s principle states that The total mechanical energy of the moving fluid comprising the gravitational potential energy of elevation, the energy associated with the fluid pressure and the kinetic energy of the fluid motion, remains constant.

Bernoulli’s equation formula is a relation between pressure, kinetic energy, and gravitational potential energy of a fluid in a container.

The formula for Bernoulli’s principle is given as:

p + 12 ρ v2 + ρgh =constant

Where,

  • p is the pressure exerted by the fluid
  • v is the velocity of the fluid
  • ρ is the density of the fluid
  • h is the height of the container
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