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Transistor as a switch any one can explain its eqn i.e Vout dec.on increase IcRc

Posted by Sangeeta Nara 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is your study strategy for the last one week before board exams ?

Posted by Snehashish Datta 5 years, 10 months ago

CBSE > Class 12 > Physics

2 answers

Raghav Ojha 7 years ago

Ncert rivisions because i think it is the mode from which sample papers are formed

Yash Tiwari 7 years ago

Practice only sample paper questions

ANSWER

Relation between mean life and decay constant?

Posted by Momena Momtaz 7 years ago

CBSE > Class 12 > Physics

1 answers

Kartik Periwal 7 years ago

Mean life is the reciprocal of decay constant

ANSWER

If we find the end of whole universe then "infinite" word exist

Posted by Akash Seth 7 years ago

CBSE > Class 12 > Physics

1 answers

Aruneeraj K 7 years ago

Finding the whole universe is not possible because universe is infinite

ANSWER

What is mean by black colour, if it is mixing of all colours then why sunlight becomes white or may be other colours?

Posted by Akash Seth 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Inside a solenoid magnetic field lines are in the form of straight lines.why??

Posted by Kartik Periwal 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

A glass lens of refractive lndex 1.45 disappear when immersed in liquid find value of refractive lndex in liquid

Posted by Amit Kumar 7 years ago

CBSE > Class 12 > Physics

2 answers

Ambuj Tiwari 7 years ago

1.45

Aruneeraj K 7 years ago

The refractive index of liquid must be 1.45

ANSWER

Derive an expression for the electric potential at any point along the axial line of an electric dipole

Posted by Zddi Siso 7 years ago

CBSE > Class 12 > Physics

1 answers

Devang Srivastava 5 years, 10 months ago

No, use your text book

ANSWER

I m not able to calculate the power question , like 3*10to the power -10/(10*10to the power 2)whole squre

Posted by Nayan Roy 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

is derivation is sufficent to get a good score in physic board exam as i am not good in this subject what can i do to score well?

Posted by Akhil Garg 7 years ago

CBSE > Class 12 > Physics

4 answers

Akhil Garg 7 years ago

i got depressed when i read previous year question papers because i am not able to answer ??

Akhil Garg 7 years ago

but i got only 2 derivations in my pre board and whole paper is full with numericals ??

Amit Kumar 7 years ago

Derivation and reasoning. Carry 40-50 marks

Aruneeraj K 7 years ago

Yes derivations are very much important

ANSWER

any suggestion for preparation in these 3 days..

Posted by Sanya Bhatia 7 years ago

CBSE > Class 12 > Physics

1 answers

Sakshi Jain 7 years ago

I can't have suggestion but i wanna told you that till you have 72 hours to prepare so go and do your best All the best????

ANSWER

Is the extra information given in blue boxes of ncert important from examination point of view?

Posted by Asmita Khati 7 years ago

CBSE > Class 12 > Physics

2 answers

Rahul Prajapati 7 years ago

Its for our knowledge

Rahul Prajapati 7 years ago

No

ANSWER

Why a beam of white light passing through a hollow prism does not give spectrum?

Posted by Devansh Verma 7 years ago

CBSE > Class 12 > Physics

1 answers

Rahul Prajapati 7 years ago

Mu doesnot change

ANSWER

Important topics for 1,3,4,6,2 units in phy.

Posted by Gaytri Devi 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Lyman series

Posted by Sourav Kumar 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

In physics, mujhe NCERT me sabse phle kya krna chaiye "examples" or "back exercise questions". Board Exam me NCERT se jo questions aate h vo examples me se jyada puchhe jaate h ya back exercise questions me se ??

Posted by Mayank K. Mahour 7 years ago

CBSE > Class 12 > Physics

3 answers

Kalas Sahu 7 years ago

Both are important

Pradeep Jangid 7 years ago

Examples are most important

Abc Kamboz 7 years ago

Back questions me se

ANSWER

Calculate the value of r in the wheatsonw vridge

Posted by Hana Amal 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Hhh

Posted by Shankar Mohanty 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Normal shift, lateral shift, transistor as a switch, transistor as an oscillator, fresnel and fraunhoffer diffraction, interference by thin film, shift in fringes, davission and germar experiment. Are these topics in syllabus for boards 2018-2019

Posted by Chesta Jain 7 years ago

CBSE > Class 12 > Physics

2 answers

Riya Singhal 7 years ago

Transistor as a switch and oscillator is not included in syllabus

Harsh Chhillar 7 years ago

Yes

ANSWER

How internal resistance of a cell vary with temperature

Posted by Sonu Sharma 7 years ago

CBSE > Class 12 > Physics

1 answers

Nikhil Sharma 7 years ago

Decreases

ANSWER

Briefly explain about cyclotron

Posted by Priyanshu Singh 7 years ago

CBSE > Class 12 > Physics

1 answers

Arti Vishwakarma 7 years ago

It is a device which is used to accelerate having a charge particles upto maximum kenetic energy. It is on the principal of moving charge in magnetic field , a charge particles can be a accelerate to high speed by passing its again and again through small region of oscillating electrical field by making the use of strong normal magnetic field.

ANSWER

By doing only 5 previous year papers are suffient to get good marks in physics

Posted by Anandu Nair 7 years ago

CBSE > Class 12 > Physics

2 answers

Devang Srivastava 7 years ago

No

Naman Kamboj 7 years ago

Yes i am satisfied

ANSWER

What is magnetic hysteris

Posted by Aaditya Goswami 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Why sun appears red at sunshine and sunset?

Posted by Kitto70787 Kitto70787 7 years ago

CBSE > Class 12 > Physics

2 answers

Piyush Chauhan 7 years ago

Due to large wavelength of red colour and shortest distance between the earth and the sun. The Scattering of red light is minimum according to Rayleigh law therefore sun appears to be red at the time of sun set and sun rise

Nitish Sharma 7 years ago

Otmospheric Refraction

ANSWER

Differentiate between conductor, semiconductor, insulator

Posted by S F Mulla Mulla 7 years ago

CBSE > Class 12 > Physics

1 answers

Vikash Kumar Gupta 7 years ago

Conductor:- The material through which electricity can pass easily. Insulator:- The material through which the electricity cannot pass. Semiconductor :- The material through which electricity can pass partially.

ANSWER

Easy way to solve 1.6×10^-19×3×10^4

Posted by Sunita Sharma 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is the intensity of electromagnetic wave?

Posted by Ajay Dhillon 7 years ago

CBSE > Class 12 > Physics

1 answers

Gaurav Seth 7 years ago

Intensity of electromagnetic wave is defined as the energy crossing per second per unit area perpendicular to the direction of propagation of electromagnetic waves.

The intensity of electromagnetic wave at a point is

where ,


and c is the velocity of electromagnetic wave.


Here E₀ and B₀ are maximum values of electric field and magnetic field respectively.

ANSWER

A ray which can use in medicle tools

Posted by Gaurav Kotecha 7 years ago

CBSE > Class 12 > Physics

4 answers

Piyush Chauhan 7 years ago

X rays and gamma rays

Chirag Raghwanshi 7 years ago

Uv rays are used for sterilisagion of medical tools

Kaursimran Simmu 7 years ago

infra red, x-rays and gamma rays

Shubham Singh 7 years ago

Infra red

ANSWER

Hysteris law

Posted by Aakarshan Bhardwaj 7 years ago

CBSE > Class 12 > Physics

1 answers

Shubham Singh 7 years ago

Charging and discharging of transformer cycles

ANSWER

Derive an equation for power combination in series (1/P=1/P1. + 1/P2)and in parallel. (P=P1 +P2).

Posted by Vikash Kumar 7 years ago

CBSE > Class 12 > Physics

0 answers

ANSWER

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