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Two point charges having equal charges separated by 1m distance experience a force of 8N . What will be the force experienced by them, if they are held in water, at the same distance? (Given: Kwater = 80)

Posted by Krishna Prava 3 years ago

CBSE > Class 12 > Physics

1 answers

Anjan Karthi 3 years ago

F = 8 = Q^2/4πε°R^2. Therefore, F' (water) = Q^2/4πε°εr R^2 = 1/80 times F. //

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Posted by Himanshu Rajput 2 years, 11 months ago

CBSE > Class 12 > Physics

5 answers

Account Deleted 3 years ago

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Himanshu Rajput 3 years ago

Tum Brahman ho ki kya ho pgl ho

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Himanshu Rajput 3 years ago

Plzz yaar 🙏

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Himanshu Rajput 3 years ago

Ok but where r u from

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Aseem Mahajan 3 years ago

<font face ="Times New Roman">Nobody asked.

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Koi sample paper buy kiya h plzz de do

Posted by Himanshu Rajput 3 years ago

CBSE > Class 12 > Physics

1 answers

Aman Deep 3 years ago

Is aap pr ata to h sample ppr 🙄

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find the focal length of a convex lens of equal radii of surface 10cm equal to 10cm and the refractive index of the material is 1. 5

Posted by Vartika Pandey 3 years ago

CBSE > Class 12 > Physics

5 answers

Mahak Mahak 3 years ago

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Vartika Pandey 3 years ago

Please give me full explanation of the question it's urgent

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Himanshu Rajput 3 years ago

Vartika where r u from

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Dibyajyoti Sahoo 3 years ago

Lens maker formula apply karo..

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Prakash Kumar 3 years ago

Kaise

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TO INVESTIGATE THE DEPENDENCE OF THE ANGLE OF DEVIATION ON THE ANGLE OF INCIDENCE USING AHALLoW PRISM FILLED ONE BY ONE WITH DIFFERENT TRANSPARENT FLUIDS

Posted by Dharshini Priya 3 years ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

Prisms can be made from any material that is transparent to the wavelengths for which they are designed. Typical materials include glass, plastic and fluorite.

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Important questions for atom chapter

Posted by Radhika Poojari 3 years ago

CBSE > Class 12 > Physics

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Magnetic moment of a single-turn current loop of aluminium wire of area A,carrying a current I in a wire of diameter d is

Posted by Prince Maurya 3 years ago

CBSE > Class 12 > Physics

1 answers

Anjan Karthi 3 years ago

M = IA.

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A proton deutron and alpha particular are accelerated through same potential difference find ratio of their kinetic energy and orbit

Posted by Aman Sharma 3 years ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

Kinetic energy gained by charged particle of charge q when accelerated under a potential difference V will be KE=qV
For a given V,KE∝q
For proton, deuteron and α-particle the ratio of charges is 1:1:2

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to investigate the dependence of angle of deviation on angle of incidence using a hollow prism filled one by one, with different transparent fluids

Posted by Tanish Batla 2 years, 6 months ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

Results of Project to investigate the dependence of angle of deviation on angle of incidence using a hollow prism filled one by one with different transparent liquids is as follows;

The angle of minimum deviation for –

Water D = 23⁰C

Kerosene oil D = 33⁰C

Turpentine oil D = 32⁰C

The refractive indices of the-

Water n = 1.32

Kerosene oil n = 1.46

Turpentine oil n = 1.44

Speed of light in-

Water v = 2.3x10 m/s

Kerosene oil v = 2.05x10 m/s

Turpentine oil v = 2.08x10 m/s

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A convex lens made of glass of refractive index 1.5 has a power of 10D in air.If it is immersed in a liquid of refractive index 1.5 the power of lens is?

Posted by Veda Sri Rasamsetty 3 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Anjan Karthi 3 years, 1 month ago

Zero. P = 1/f = (n of liquid/n of glass - 1) 1/R1 + 1/R2 = (1.5/1.5 - 1) 1/R1 + 1/R2 = 0.

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Sophie s dreams and disappointments are all in her mind

Posted by Shivu Gayri 3 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years, 1 month ago

Sophie was a dreamer who often made up stories for herself and for others. One possibility might be that she wanted to escape the squalor of daily life with the help of her fantasies. Her encounter with Danny Casey was a made-up story for the sake of catching her brother’s attention. Eventually, she gets so much engrossed in it that she starts to live the fantasy. When Danny Casey does not arrive for the second ‘date’, she experiences disappointment. However painful and disappointing her fantasy might be, she was not willing to accept reality. Her dreams and disappointments are figments of her imagination.

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Mirage

Posted by Wiza Aphi 3 years, 1 month ago

CBSE > Class 12 > Physics

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What is the transverse nature of Electromagnetic waves ?

Posted by Ritesh Sharma 3 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Anjan Karthi 3 years, 1 month ago

In electromagnetic waves, the direction of oscillation of the accelerated source charged particle is perpendicular to the direction of propagation of the wave. This is called the transverse nature of electromagnetic waves. In other words, the alternating electric and magnetic fields produced as a result of oscillation of the particle are mutually perpendicular to each other and to the direction of propagation of the wave.

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Surya Chouhan 3 years, 1 month ago

Transparent

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To determine resistance per cm of a given wire by plotting a graph for potential difference versus current.

Posted by Soumyadeep Dafadar 3 years ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

The process to determine resistance per cm of a given wire by plotting a graph of potential difference versus current is given below.

If you plot the potential difference along the X-axis and the current along the Y-axis, the reciprocal of the slope gives the material's resistance, R.
If you interchange the quantities on the axes, the resistance will be given by its slope and not it's reciprocal.
The resistance per cm is given by R/l if the length of the resistance wire is 'l' cm.

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Koi my cbse guide ka sample paper kharida h 12th ka please 🙏 share kr de bhai

Posted by Rounak Anand 3 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Ritesh Rai 3 years, 1 month ago

Hme bhi send kr do bhai

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Rounak Anand 3 years, 1 month ago

Bhai apna phone no. Do na

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Poojar Panchal 3 years, 1 month ago

Yes bhai

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Ch 1 notes

Posted by Priya Kumari 3 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Divya. Kumari 3 years, 1 month ago

Yess

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Prakash Kumar 3 years, 1 month ago

Jiii

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Priya Kumari 3 years, 1 month ago

Notes ch 1

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What is radiowaves

Posted by Vinay Pratap Singh 3 years ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

Radiowaves are electromagnetic waves and are produced by oscillating electronic circuits. The frequency range of radiowaves is from 3 {tex}\times{/tex} 10³ to 3 {tex}\times{/tex} 10¹¹ Hz.
Uses

They are used in wireless communication to transmit radio and TV signals.
Radiowaves are used in radioastronomy.

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Lens maker formula and prism

Posted by Kuldeep Raj 3 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kashu Verma 3 years, 1 month ago

The lens maker formula is 1/f=(u-1)[1/R^1-1/R^2]

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Explain Einstein's theory of photoelectric effect.

Posted by .. .... 3 years ago

CBSE > Class 12 > Physics

1 answers

Preeti Dabral 3 years ago

Photoelectric effect: When certain metals are exposed to a beam of light, the electrons are ejected from the metal. This phenomenon is called the photoelectric effect. The electrons ejected are called photoelectrons.

The results of this experiment were:

The electrons are ejected from the metal surface as soon as the beam of light strikes the surface, i.e., there is no time lag between the striking of the light beam and the ejection of electrons from the metal surface.
The number of electrons ejected is proportional to the intensity or brightness of the light.
For each metal; there is a minimum frequency, {tex}\nu_o{/tex} below which photoelectric effect is not observed.
K.E. of electrons {tex}\propto{/tex} frequency of light.

Equipment for studying the photoelectric effect. Light of a particular frequency strikes a clean metal surface inside a vacuum chamber. Electrons are ejected from the metal and are counted by a detector that measures their kinetic energy:

Explanation of photoelectric effect on the basis of quantum theory: When a photon of sufficient energy strikes an electron in the atom of the metal, it transfers its energy to the electron and the electron is ejected without delay. Greater the energy of the photon, greater will be the kinetic energy of the ejected electron.

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CBSE Class 12 physics Important Questions Chapter 14 Electronic Devices 1 Mark Questions 1.Give the ratio of number of holes and the no. of conduction electrons in an intrinsic semiconductor. Ans.(As in intrinsic semiconductor ne = nh) 2.What type of impurity is added to obtain n-type semiconductor? Ans. Pentavalent atoms like Arsenic (As) 3.Doping of silicon with indium leads to which type of semiconductor? Ans.Indium is a trivalent impurity, thus doping of silicon with indium leads to p-type semiconductor. 4.Draw an energy level diagram for an intrinsic semiconductor? Ans.In intrinsic semiconductor (ne = nh) 5. A semiconductor has equal electron and hole concentration of. On doping with a certain impurity electron concentration increases to. Identify the type of semiconductor after doping? Ans.As ne > nh, thus resulting semiconductor is of n-type. 6.How does the energy gap of an intrinsic semiconductor vary, when doped with a trivalent impurity? Ans. When a trivalent impurity is added to an intrinsic semiconductor, an acceptor energy level is created in the forbidden energy gap which lies above the valence band. Due to this electrons easily transformed to the acceptor energy level. 7. How does width of depletion layer of p.n junction diode change with decrease in reverse bias? Ans.Decrease in reverse bias will decrease in width of the depletion layer. 8. Under what condition does a junction diode work as open switch? Ans. A junction diode works an open switch when it is reverse biased. 9. Which type of biasing gives a semiconductor diode very high resistance? Ans.Reverse biasing

Posted by R.L. Trivedi 3 years, 1 month ago

CBSE > Class 12 > Physics