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what is relative permitivity

Posted by Anup Soni 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Shubham Chy 6 years, 11 months ago

The permitivity of a medium with respect to air is called relative permitivity

1Thank You

Yogita Ingle 6 years, 11 months ago

Relative permittivity e(r) is defined as the ratio of absolute permittivity of a medium (e) to the absolute permittivity of free space (e0)
e(r) = e / e0
It can also be defined as the the ratio of forces of attraction/repulsion between two point charges separated by a certain distance in vacuum to the force of attraction when they are placed in a medium same distance apart.
e(r) = F(o) / F(medium)Clearly relative permittivity is a unitless constant.

2Thank You

ANSWER

Geometrical optics syllabus me hai ya nahi physics 12th ke

Posted by Harshit Tiwari 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Ladi Rahil 6 years, 11 months ago

11th ka h

0Thank You

ANSWER

Define power of lens

Posted by Pinto Kumar 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

When we throw a ball ,the ball turn w.r.t hand or in opposite direction of hand

Posted by Priyanshu Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Is ncert sufficient for physics

Posted by Robin Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

4 answers

Tushar Kumar 6 years, 11 months ago

Use modern abc of Satish k gupta only but read out ncert topics only which will help u to get 90 above.

1Thank You

Aditya Raj 6 years, 11 months ago

But for theory, you should read - resnik halliday (old edition).

1Thank You

Chesta Gupta 6 years, 11 months ago

U can also refer irodov and resnik haliday

1Thank You

Aditya Raj 6 years, 11 months ago

No, Do H.C.Verma or cingage for best complement.

1Thank You

ANSWER

Who can understand physics?

Posted by Satpal Bansal 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Tushar Kumar 6 years, 11 months ago

One who practice daily which was taught in the class?‍??‍?

2Thank You

ANSWER

An object is kept in front of a concave mirror of focal length 15 cm. The image formed is real and three times the size of the object. Calculate the distance of the object from the mirror

Posted by Nishi Giri 5 years, 10 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How to study physics

Posted by Paras Kundu 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Tushar Kumar 6 years, 11 months ago

Physics is the only standard and lengthy subject in the syllabus so study the selected topics of ncert from any side book and study daily whatever your teacher taught in the class

1Thank You

Ayush Verma 6 years, 11 months ago

Slowly and understand with imagination

1Thank You

ANSWER

Who is the father of science ?

Posted by Riyã Sháh 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Tushar Kumar 6 years, 11 months ago

Galileo galilei is considered as the father of science as he contributed more to science

2Thank You

ANSWER

Is there ray optics still present in syllabus?

Posted by Lakshaya Kansal 6 years, 11 months ago

CBSE > Class 12 > Physics

3 answers

Aditya Raj 6 years, 11 months ago

No! Surely.

0Thank You

Ayush Verma 6 years, 11 months ago

Not sure yet for 2019-20

0Thank You

Kate Disuja 6 years, 11 months ago

Yes

0Thank You

ANSWER

the projection of vector r = 3i+j+2k on the x y plane has magnitude

Posted by Gaurav Raj 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How we can identify body is charged

Posted by Nirbhay Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Tushar Kumar 6 years, 11 months ago

We can identify it by bringing another charged body near to it .The charged body experience a force which proves the body is charged

1Thank You

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Two identical balls with equal charge are kept 4.5cm apart. The force between them increases by 10% on giving extra charge of 0.001×10^-6C to one of the ball . Calculate the charge on each ball?????? Sollutoin plz...

Posted by Swastik Sharma 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is culoumbs law of electrostatics??

Posted by Muhammad Akhtar Raza 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 11 months ago

Coulomb’s law states that Force exerted between two point charges:

Is inversely proportional to square of the distance between these charges and
Is directly proportional to product of magnitude of the two charges
Acts along the line joining the two point charges.

0Thank You

ANSWER

What is motion of satellites

Posted by Shubham Agrawal 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Astha Dewangan 6 years, 11 months ago

Motion of satellites is projectile in motion

0Thank You

ANSWER

एक चिड़िया घर में मोर और चीता रहते हैं उनके सिर की संख्या 400 और उनके पैरों की संख्या 1160 मोरों की संख्या बताइए

Posted by Rajpalsingh Rajpal 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Nand Mohan Jha 6 years, 11 months ago

Let the no. of peacock is x the no. of cheeta is y Now According to question X + Y =400 2X + 4Y =1160 by solving these two linear equations We get Y = 180 X = 220

1Thank You

ANSWER

Which of the following waves can be polarized (i) heat wave (ii) sound wave ?

Posted by Himanshu Arya 6 years, 11 months ago

CBSE > Class 12 > Physics

3 answers

Sahil Kharb 6 years, 11 months ago

Heat Wave Posted by Sahil Kharb

0Thank You

Nand Mohan Jha 6 years, 11 months ago

Heat wave can be polarized because it is transverse wave and sound wave is longitudinal wave

1Thank You

Raghav 009 6 years, 11 months ago

Heat wave

1Thank You

ANSWER

What are permanent magnets ? Give one example

Posted by Himanshu Arya 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Kawalpreetsingh Sandhu 6 years, 11 months ago

Magnets possess higher retentivity ( ability to keep magnetization) and coercivity ( magnet field intensity at which magnet lost magnetization) and retain the magnetic field for long period are called permanent magnets. Example : Alnico , steel etc..

0Thank You

Lucky Singh 6 years, 11 months ago

Fe2O3

0Thank You

ANSWER

How to study physics , its so tough????

Posted by Paras Kundu 6 years, 11 months ago

CBSE > Class 12 > Physics

4 answers

Saagu Gopi 6 years, 11 months ago

Never give up

2Thank You

Yakshi Baliyan 6 years, 11 months ago

don't take it as tough subject... feel it , enjoy it...and the main thing is u can imagine most of the things in physics while it is not possible in chemistry physics is a good subject i love it but don't know why i don't become able to good marks? but still love it....it is interesting i love understanding concepts but i hate numericals?

3Thank You

Paras Kundu 6 years, 11 months ago

So funny????

3Thank You

Devisha Singh 6 years, 11 months ago

Don't study then☺ It's okay

2Thank You

ANSWER

A charged spherical conductor has a surface density of 0-07 C cm2 When the charge is increased by 4.4 C, the surface density changes by 0.084 C cm2. Find the initial charge and capacitance of the spherical conductor.

Posted by Anjali Kapre 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Two metalliv spheres a and b kept on insulating stands are in contact with each other. A positively charged rod p is brought near the sphere a . Both spheres are separated from each other and the rod p is removed. What will be the nature of charges on a and b

Posted by Princi Jaiswal 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Aditya Raj 6 years, 11 months ago

I guess sphere is also positively charged.

0Thank You

ANSWER

A charged wire of length L lies along x axis in such a way that its linear charge density is given by lembda equal to ax square where a is constant .calculate charge on the wire

Posted by Anku Yes 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Tushar Kumar 6 years, 11 months ago

Linear charge=q/l. ----1 But it is given that ,linear charge=ax**2. ----2 From eq 1&2,we have q=l*ax**2C {*=Multiply} {**=Exponent}

0Thank You

Prakhar J 6 years, 11 months ago

ax^2×l coulomb, where l is the length of the wire

0Thank You

ANSWER

consider three charges q1 q2 q3 each of charge q at vertices of equalateral triangle of side l . what is the force on a charge Q on the centroid of the triangle

Posted by Jai Singh 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Ritik Ranjan 6 years, 11 months ago

Zero

0Thank You

ANSWER

What is the difference between source charge and test charge?

Posted by Komal Sehwag 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Tushar Kumar 6 years, 11 months ago

A charge which is having electric lines of force constituting electric field around itself is called source charge on the other hand test charge is positive and of vanishingly small magnitude which do not affect the electric field of source charge

2Thank You

Yogita Ingle 6 years, 11 months ago

The charge which is the cause of electric field in space is called source.
A test charge is a positive charge of very small magnitude which gives the direction and strength of electric field in space without influencing the electric field.

1Thank You

ANSWER

3 cells are connected in parallel with their wires of negligible resistance if the emf of the cells are 2,1,4v and if their resistance are 1:3:3 find current

Posted by Jogaram Lomror 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Harsh Tiwari 6 years, 11 months ago

2Thank You

ANSWER

What is the real law

Posted by Satyam Kumar 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is coloumbs law?

Posted by Anuvav Thakur 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Ayush Verma 6 years, 11 months ago

Acc to this, the force of attraction or repulsion between two stationary point charges is directly proportional to product of their magnitude and inversely proportional to square of distance between them.

1Thank You

ANSWER

Define coulomb

Posted by Rashmita Behera 6 years, 11 months ago

CBSE > Class 12 > Physics

1 answers

Prakhar J 6 years, 11 months ago

Coulomb is the amount of charge....

1Thank You

ANSWER

A tower has height of 80 cm. How much height of tower should be increased to triple It's coverage.

Posted by Pranish Moukhede 6 years, 11 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is super position principal

Posted by Arpit Kumar 6 years, 11 months ago

CBSE > Class 12 > Physics

2 answers

Prakhar J 6 years, 11 months ago

F( total) = q°/(4π€°)× sigma from i=1to n....q(i) / r^2(i)

0Thank You

Prakhar J 6 years, 11 months ago

Super position principle states that amount of force exerted by a collection of charges on a testing charge is equal to the vector sum of all the forces caused individually.

0Thank You

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