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Two wires

Posted by Rakshit Jain 2 years, 8 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 8 months ago

complete your question.

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50 gram of steam at 100 degree celsius is passed into an insulated container containing 50 gram of ice at minus 5 degree Celsius and 50 gram of water at 60 degree celsius is mixed with it find the equilibrium temperature and decomposition of the mixture

Posted by A J 2 years, 8 months ago

CBSE > Class 11 > Physics

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The colour of blackbody is necessary to be black or not. Why?

Posted by Pari Mavi 2 years, 8 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 8 months ago

No, it is not necessary that all black coloured object should be considered as black bodies. For example , if we take a black surface which is highly polished, it will not behave as a perfect black body .

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The colour of blackbody is necessary to be black or not?

Posted by Pari Mavi 2 years, 8 months ago

CBSE > Class 11 > Physics

3 answers

Preeti Dabral 2 years, 8 months ago

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Inzmam Butt 2 years, 8 months ago

Thnks

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Surya Pratap Singh 2 years, 8 months ago

Colour doesnt depend sun is a black body To be a black body a thing should be good emitter as well as good absorber

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On heating a conductor electron gets excited and they start to move then why current does not produce while the electron moving?

Posted by Pari Mavi 2 years, 8 months ago

CBSE > Class 11 > Physics

0 answers

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Why Stefan's law is also known as Stefan's Boltzmann Law?

Posted by Pari Mavi 2 years, 8 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 8 months ago

The Stefan–Boltzmann law, also known as Stefan's law, states that the total energy radiated per. unit surface area of a black body in unit time (known variously as the black-body irradiance, energy flux density, radiant flux, or the emissive power), j*, is directly proportional to the fourth.

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What is dimensions of density

Posted by Prasad Rathod 2 years, 9 months ago

CBSE > Class 11 > Physics

2 answers

Ishan Ishan 2 years, 9 months ago

MLT0

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Jatin Choudhary 2 years, 9 months ago

M1L-3T0

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Posted by Tejasri Sahu 2 years, 9 months ago

CBSE > Class 11 > Physics

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What is the si unit of distance

Posted by Namrata Biswas 2 years, 9 months ago

CBSE > Class 11 > Physics

5 answers

Preeti Dabral 2 years, 9 months ago

The SI unit of distance is metre. Q. The SI unit for both distance and displacement is metre.

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Shanika Sharma 2 years, 9 months ago

Meter

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Khushi Choubisa 2 years, 9 months ago

Metre

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Neharika Thakur 2 years, 9 months ago

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Vikesh Singh 2 years, 9 months ago

the si unit of distane is meter/m

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A moving particle of mass m makes head on elastic collision with a particle of mass 2m . Which is initially at rest so that the colliding particles loose 8/9 of its energy after collision.

Posted by Shikha 🤫 2 years, 9 months ago

CBSE > Class 11 > Physics

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2 25w

Posted by Harshu Katiyar 2 years, 9 months ago

CBSE > Class 11 > Physics

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1 light year

Posted by Satya Ranjan Tulu 2 years, 9 months ago

CBSE > Class 11 > Physics

2 answers

Jatin Choudhary 2 years, 9 months ago

9.46*10**15

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Shanika Sharma 2 years, 9 months ago

A light year is the distance light travels in one year (365 days).

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What is the relation between linear expansion superficial expansion and volume expansion of a solid

Posted by Shanika Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 9 months ago

It is generally accepted that if the coefficient of linear expansion is the same in all directions for a given material, then the coefficient of superficial expansion is approximately twice the coefficient of linear expansion and the coefficient of cubical expansion three times the coefficient of linear expansion.

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Water flows through a horizontal pipe line of varying cross section at the rate of 0.2m³/sec. Calculate the velocity of water at a point where the area of cross section of pipe is 0.02 m ².

Posted by Shanika Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 9 months ago

{tex}\begin{aligned} & v=\frac{\text { Rate of flow }}{a} \\ & \text { Rate of flow }=0.2 \mathrm{~m}^3 \mathrm{~s}^{-1} a= \\ & v=\frac{0.2 \mathrm{~m}^s \mathrm{~s}^{-1}}{0.02 \mathrm{~m}^2}=10 \mathrm{~ms}^{-1} \end{aligned}{/tex}

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One end of a copper rod 0.6 m long and 2×10¯³ m in radius is kept in boiling water at 100 c the other end is kept in ice at zero degree celsius. If 7.2×10¯² kg of ice melt per hour. Calculate thermal conductivity of copper.

Posted by Shanika Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

0 answers

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How to prove gravitational force is a conservative force?

Posted by Nishant Rajput 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Shanika Sharma 2 years, 9 months ago

Gravitational force is a conservative force because the work done against gravity is always conserved. For example: when we throw an object vertically above to the height of h metre then the work done against the gravity is W'=mgh where, mass of the object =m height =h acceleration due to gravity =-g and when the object falls back from the same height the work done is w" = mgh Here the total work done, W=W'+W"\ W=-mgh+mgh=0 Hence the total work done in travelling certain height and falling back to same place is zero, this is the property of conservative ford as the total work done depends only on the initial and final position of the object. Since the distance travelled is zero, the work done must be zero which is the same here. That's why gravitational force is a conservative force. Forces that do not store energy are called non-conservative of dissipative forces. Friction force is an example of a non-conservative force because it do not store energy rather than storing it. Frictional force oppose the motion of the object i.e. f i ∝ − Δ r i Thus the net work done by frictional force is negative as, Δ W = ∑ i f i Δ r i = − ∑ i | f i | ri|<0 Negative sign indicates that the frictional force continually drains energy from the object as it moves over the surface . So it disipates energy in the form of heat.

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What is reflecting and transmitting power of a perfectly black body?

Posted by Shanika Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Sakshi Masal 2 years, 9 months ago

the reflecting and transmitting power of a perfectly black body is 1,as it reflects the same amount of energy it absorbed.

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Initial velocity of a projectile is 20 metre per second at 60 degree angle what is its velocity at maximum point

Posted by Pardeep Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Sakshi Masal 2 years, 9 months ago

as the body slow downs to zero at maximum point , the velocity at max point/height is 0.

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r second at 60 degree angle what is its velocity at maximum point

Posted by Pardeep Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Galaxy Threpy 2 years, 9 months ago

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Si unit of heat

Posted by Tushar Kumar 2 years, 9 months ago

CBSE > Class 11 > Physics

3 answers

Shanika Sharma 2 years, 9 months ago

Joule

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Guru Banu 2 years, 9 months ago

Joule

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Anshi Bidhuri 2 years, 9 months ago

Joule(J)

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Law of angular momentum

Posted by Methli Sharma 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Shanika Sharma 2 years, 9 months ago

It is defined as the product of linear momentum of the partical and the perpendicular direction of the particle from axis of rotation . L=r×p L=rp sin Q SI unit =kg m²/sec Dimensional formula =[MLT¯¹][L] =[ML²T¯¹]

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What is conservation of energy

Posted by Rahul Yadav 2 years, 9 months ago

CBSE > Class 11 > Physics

2 answers

Gopi Kishan Kumar 2 years, 9 months ago

that energy can neither be created or not be destroyed

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Mitali Sharma 2 years, 9 months ago

that energy can neither be created or not be destroyed..

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A new unit of length is chosen such that the speed of light in vacuum is unity what is the distance between the sun and the earth in terms of the new unit if light takes 8 Minute and 20 second to cover this distance

Posted by Rohit Kumar 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 9 months ago

The speed of light in vacuum (c) = 1 new unit of length s^-1
Time taken by light to reach the Earth,
t = 8 min + 20s = (8 {tex}\times{/tex} 60 + 20) s = 500 s
{tex}\therefore{/tex} Distance between the Sun and the Earth
= Speed of light {tex}\times{/tex} Time
x = c {tex}\times{/tex} t = 1 new unit of length s^-1 {tex}\times{/tex} 500 s
= 500 new units of length

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Express kinetic energy by calcalus method

Posted by Dharshan Shakresh 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Shabya Shaikh 2 years, 9 months ago

Suppose, body is initially at rest and force 'F' is applied on the body to displace it through 'ds' along it's own direction. Then small workdene, dw = f.ds dw = fds Acc. to Newton's 2nd law of motion f = ma Therefore, dw = ma ds dw = m dv/dt ds dw = m ds/dt dv dw = mvdv Integrating both sides In order to increase it's velocity from 0-v workdone is given by -- w = m sign of integration upper limit v and lower limit 0 vdv w = m[v square/2] upper limit v and lower limit 0 w = m[v square/2-0] w = 1/2mv square workdone is stored in form of energy Therefore, K.E. = 1/2mv square

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If the mass of the sun is 2 into 10 ki power 30 kilogram that the distance of the earth from the sun is 1.5 into 10 ki power 11 M and Period of the revolution of the earth around the sun is one year the value of the gravitational constant

Posted by Dhruv Pandat 2 years, 9 months ago

CBSE > Class 11 > Physics

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Dimensional variable

Posted by Naresh Pukhram 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Shanika Sharma 2 years, 9 months ago

Dimensional variable are physical quantities that have numerical value and some specific dimensions. Examples include length, velocity, and acceleration, among other.

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5 similarities between viscosity and solid friction

Posted by Abigail Lalnunnem 2 years, 9 months ago

CBSE > Class 11 > Physics

1 answers

Preeti Dabral 2 years, 9 months ago

Similarities: Both opposes relative motion. ... Viscous force depends on the velocity gradient and area of contact and frictional force independent of area of contact and relative velocity. Viscosity of liquid decrease with increase in temperature, Where as friction independent of temperature.

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If Something Is Variable We Normally Differentiate It In Physics But Why Variable Force Can't Be Differentiated

Posted by Palaniappan Subbiah 2 years, 9 months ago

CBSE > Class 11 > Physics