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Photo diode .

Posted by Kriti Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Anshu Dwivedi 6 years, 1 month ago

It is connected in reverse bised . It is mainly used to detecting of optical signal. And it increase depletion layer.

Pradeep Poonia 6 years, 1 month ago

It is connected in forward bias. When light falls on depletion layer, the neutral atoms in depletion layer breaks in hole+electron, holes move towards negetive and electrons move towards positive terminal. Hence current starts flowing. It is used in burgler alarm, note counting etc.

ANSWER

Two monochromatic radiations of frequencies v1 and v2 (v1>v2) and having same intensity are in yuen incident on photosensitive surface to cause photoelectric emission . Explain giving reason in which case more number of electrons will be emitted?

Posted by Abcd Abcd 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Pradeep Poonia 6 years, 1 month ago

same number of electrons will be emitted if both the frequencies are greater than threshold frequency. Because no. of electrons emitted depends on intensity not on frequency.

ANSWER

Modulation or usse aage wala topic syllabus me hai kya ??

Posted by Satyal Gupta 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Pradeep Poonia 6 years, 1 month ago

ye sab communication wale chapter se h jo hat gaya h syllabus se is bar

ANSWER

Can anyone plzz give the chap wise marks distribution in physics...

Posted by Neha Bhatt 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Is ncert is enough for board?

Posted by Yakuza Shimatoro 6 years, 1 month ago

CBSE > Class 12 > Physics

7 answers

Harendra Singh 6 years, 1 month ago

Yes it is enough + previous year question

Kriti Sharma 6 years, 1 month ago

No

Ishita Ishita 6 years, 1 month ago

More than enough

Ishita Ishita 6 years, 1 month ago

Yes

Simpy Jha 6 years, 1 month ago

Not at all

Aadhy Kosambi 6 years, 1 month ago

No

Rikshesh D. 6 years, 1 month ago

not actually

ANSWER

how many theoratical qustion in board exam

Posted by रावण जी 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

It is given in the book that, rate of work done= |E|.I ,can anyone please explain how this formula is generated???

Posted by Rajat Barwar 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Rajat Barwar 6 years, 1 month ago

Thank you for answer..

Pradeep Poonia 6 years, 1 month ago

Power= V×I= E×I (V or E same) Rate of workdone is power

ANSWER

R is a radius of a sperical conductet Vm the dielectric strength then the maximum electric field magnitude to which can be released

Posted by Sumit Gupta 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How many theorm and question are In paper

Posted by Mayank Chaudhary 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Rikshesh D. 6 years, 1 month ago

probaby 2 question

ANSWER

Write energy stored in a capacitor

Posted by We Are Best 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Simpy Jha 6 years, 1 month ago

Q^2 / 2C

Yuvraj Singh 6 years, 1 month ago

Enerygy stored in capacitor=1/2CV^2

ANSWER

What is the formula of heat

Posted by Punit Jangir 6 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Shivani Thakur 6 years, 1 month ago

H=i×i×r×t

Simpy Jha 6 years, 1 month ago

I square ×R × T

Nandani Tumram 6 years, 1 month ago

I(square)2×r×t

ANSWER

Describe the various methods of producing induced emf. Derive an expression for the instantaneous emf induced in a coil rotated in a magnetic field.

Posted by Sohan .G 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

se Lenz law to find the direction of induced emf in a coil when (a) a north pole is brought towards the coil (b) north pole taken away from the coll (c) A south pole is brought towards the coil and (d) south pole is taken away from the coil, draw illustrations in each case

Posted by Sohan .G 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Simple microscope topic ht gya h

Posted by Arpit Kushwaha 6 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Bhuvane Kashyap 6 years, 1 month ago

Nhi bro

Simpy Jha 6 years, 1 month ago

Nhii

Sukirti Sharma 6 years, 1 month ago

no way

Shubham Chaudhary 6 years, 1 month ago

Nhi

ANSWER

Is van de graff generator is there in syllabus..?

Posted by Soundheart Priyanshu 6 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Simpy Jha 6 years, 1 month ago

No .

Priya Sharma 6 years, 1 month ago

No

Priyanshu Sharma 6 years, 1 month ago

No

ANSWER

What is the si unit of capacitance

Posted by Raj Singh 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Arpit Kushwaha 6 years, 1 month ago

Farad

Amar Thakur 6 years, 1 month ago

Farad (F)

ANSWER

What is gold foil electroscope

Posted by Srishty Sidana 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Aryan Aryan 6 years, 1 month ago

Bakwas h ye sb

Yogita Ingle 6 years, 1 month ago

A gold-leaf electroscope is a simple device which is used to identify the electric charge present in a body.Their operation is based on the principle of like sign charge repulsion. Two sheets or leaves, cut longer than they are wide and made of very thin, electrically conductive material, are hung adjacent and virtually in contact with each other. The leaves are ordinarily made of material sufficiently thin so that they have no rigidity and hang down limply. When the leaves, which are electrically connected, become electrically charged, they push apart from each other. The angle they form correlates on the amount of electric charge on the leaves. See the figure below. If the instrument is shielded so that the capacitance is fixed, then the angle can be with some precision to static voltage. It should be noted that the electroscope actually indicates potential, not charge.

ANSWER

Mention methid of charging conducter

Posted by Chandramathi Shetty 6 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Sukirti Sharma 6 years, 1 month ago

conduction nd induction for conductors friction nd polarisation for insulators

Rajdev Aditya 6 years, 1 month ago

it is method in which conductor charges fully

Srishty Sidana 6 years, 1 month ago

Charging by friction

ANSWER

on an average kitna de dete hai i mean in practicals of all subjects

Posted by Rikshesh D. 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Sukirti Sharma 6 years, 1 month ago

28 to most of students

ANSWER

A convex lens is dipped in a liquid whose refractive index is equal to the refractive index of the lens.then its focal length will

Posted by Gayathri Ganesan 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Arpit Kushwaha 6 years, 1 month ago

Focus length decrease

Raunak Kumar 6 years, 1 month ago

Remain same

ANSWER

What is tourck

Posted by Param Tomar 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

Torque is the measure of the force that can cause an object to rotate about an axis. Force is what causes an object to accelerate in linear kinematics, similarly, torque is what causes an angular acceleration. Hence torque can be defined as the rotational equivalent of linear force. The point where the object rotates is called the axis of rotation. In physics, torque is simply the tendency of a force to turn or twist. Different terminologies such as moment or moment of force are interchangeably used to describe torque.

ANSWER

What is displacement current ?

Posted by Rishita Shishir ?✏ 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

Displacement current is a quantity appearing in Maxwell’s equations. Displacement current definition is defined in terms of the rate of change of the electric displacement field (D).
It can be explained from the phenomenon observed in a capacitor.

ANSWER

How is the diffraction pattern diffrent from interfernce pattern obtained in young,s double slit experiment

Posted by Harshit Goyal 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

Interference occurs due to superposition of two distinct waves coming from two coherent sources of light. The diffraction occurs as a result of the secondary wavelets coming from different parts of the same wavefront.
In the pattern of the interference, all the bright fringes have same intensity. In a diffraction pattern, all the bright fringes are not of the same intensity.

ANSWER

Using biot-savart's law obtain the expression for the magnetic field due to a circular coil of radius R carrying a current I at a point on it Axis distance x from the centre of the coil

Posted by Aman Barthwal 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

An Alpha particle and a Proton of same velocity V enters a uniform magnetic field at right angle the particle describe circular path find ratio of the linear momentum of given particle

Posted by Vishal Budania 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Different units of radioactivity

Posted by Vishal Budania 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 6 years, 1 month ago

The SI unit of radioactivity is becquerel (Bq) and this term has been kept after Henri Becquerel. It is defined as:

The activity of a quantity of radioactive material where one decay takes place per second

1 becquerel = 1 radioactive decay per second = 2.703×10^-11

An older radioactivity unit is the curie (Ci) and the name has been taken from Pierre and Marie Curie.

It is defined as that quantity of any radioactive substance which gives 3.7 X 10¹⁰s^-1 disintegration (dps).
Sometimes millicurie (mc) and microcurie (mc) are also used.

ANSWER

How electron electron attract each other with gravitational force

Posted by Srishty Sidana 6 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ashirwad Kumar 6 years, 1 month ago

Since electrostatic force is greater than gravitational force

ANSWER

What questions are asked to you by your external examiner in final practical. Please share.......... Of Every subject .......?

Posted by Kriti Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

33 answers

Shivani Thakur 6 years, 1 month ago

Is there anyone..???

Shivani Thakur 6 years, 1 month ago

Are yr..sbne leave kr diya ..kya?

Shivani Thakur 6 years, 1 month ago

*rohan...be better tempered ?????

Shivani Thakur 6 years, 1 month ago

Nd to aal oters for their aims.....and ya everyone take care of urselves also?....kitna achcha hota agr phr kbi mil paye!!

Shivani Thakur 6 years, 1 month ago

So....best of luck for boards everything ??...nd for ur neet entrance also darshaana....dost....for ur ssb rohan ??...wish u.all the ??best...

Shivani Thakur 6 years, 1 month ago

Thanks everyone..daarshana....rihan...for every advice......annd soooory also..????...rohan nd aman agr bura lga ho too...aap sb log exit le..rhe ho..??....

Kriti Sharma 6 years, 1 month ago

Thanks everyone . .... Be friendly with each other ...... Don't be arrogant...... Be friends...thanks aman .......darshana......shivani.......mannat......gopal......rohan......aryaman............ishika....???

Rohan Řąjpůť 6 years, 1 month ago

ohk anything else. ??BTW itna sry Rohan Rajput kisi ko ni bolta jitna tumko bola Miss Darshana yadav... but still tumhe kuch fark he nhi hua. ?? bye. I will not answer unless from toady onwards.

Ďãřşháñăã Yadav ? ? ? 6 years, 1 month ago

and I am not apologies for this rude lage toh lagne do. thanks.

Ďãřşháñăã Yadav ? ? ? 6 years, 1 month ago

I am requesting to the users that don't post unnecessary answers which leads to long conversation as it distract the topic. if they want to suggest something in favour of the topic they can.. otherwise they may go offline. I am requesting this from both of you. (Aman and Rohan)

Shivani Thakur 6 years, 1 month ago

Organic chemistry se.....amines chap. Se poche the question....for ex-aniline and ethanamine se..less basic konsa h..nd why...rasonating syructure kis way m ise effect krta h??....nd monomeric units of polymer sss from polymer chaptet...don't u woory aallll...bhot achcha hoga?????..best of luck for everyone ?

Shivani Thakur 6 years, 1 month ago

Salt analysis..jo aapnr kiye h..nd yya one more thing...jo salt hota h....firstly vhi ni bya dena hota h?....aap sb log jante hpnge..bt kbi,kbi ho jata h...kuch bachcho m kiya tha isliye?..

Shivani Thakur 6 years, 1 month ago

Nd ya i agree vth darshanna ...same here....hmare practicals ho b chuke h nd achcje hue bhoot ????.....so normal logical question poche jate h...apni file ko properly prepare kro nd koi b 2-3chaptets ....dhang se bt.....

Shivani Thakur 6 years, 1 month ago

Areeeee...yr tum log to pyar -ppyar se lde hi ja rhe ho.....rohan..yr it's not pak..border yrr...it's ok..choodo na...mana tumne apna point rakha bt...☺??..just calm down everyone ?

Ďãřşháñăã Yadav ? ? ? 6 years, 1 month ago

thanks mannat... ? ? ? but mere kaam ka nhi I am neet aspirant... Jiska bhi hai all the best for ur result hope ke unka result accha aaye. ????

Mannat Kaur Khalsa?? 6 years, 1 month ago

Hey....jee result is out

Gopal Mishra 6 years, 1 month ago

You must to learn all devices principal and project topic also

Ďãřşháñăã Yadav ? ? ? 6 years, 1 month ago

Mere practical abhi start nhi hue... but as per my teacher instructions prepare at least 2 chapters ... u should have knowledge about ur investigatory project and at last all the practicals which u had mention in ur file should be on ur tips. hope it help ✌️ I will definitely inform u about my practical viva question.

Rohan Řąjpůť 6 years, 1 month ago

bhai arrogant feel hota toh tu yaha reply nhi kr raha hota... becoz mera jawab la jawab hota. mind it. ?

Rohan Řąjpůť 6 years, 1 month ago

Jo type krna hai kro, Jo puchna hai pucho

Rohan Řąjpůť 6 years, 1 month ago

bhai itna tym nhi hai mere pass ke subki tension Lunga... aur still fir bhi sense yahi hai.. baaki tum log, tumhara mann Maine Konsa WiFi ka charge krna hai tumhara.

Aryaman Chauhan 6 years, 1 month ago

Simple basic principles

Amol Gùpta 6 years, 1 month ago

Aaj chemistry ka diya kl bio ka h

Amol Gùpta 6 years, 1 month ago

Arrey yrr kch nhi dimag kharab ho gya 2 2 practical ek saath dekr

Rohan Řąjpůť 6 years, 1 month ago

instead of kyuki it's kyu *

Amol Gùpta 6 years, 1 month ago

Rohan it's okk

Amol Gùpta 6 years, 1 month ago

And from physics my topic was moving coil galvanometer from that - How it works , current sensitivity voltage sensitivity and if we talk about my friends they told me that he asked chapter names questions related to the experiment

Amol Gùpta 6 years, 1 month ago

My topic was haloarenes so he asked reactions related to that , reactivity like which is more reactive and why that's it

Rohan Řąjpůť 6 years, 1 month ago

logo*

Rohan Řąjpůť 6 years, 1 month ago

subke yaha same external thode na aayenge. ??? kya lga rakha hai share question share question... subke question different honge puchne ke as sub teacher same ni hote. ?? as a 12th standard student itna minds toh hona he chahhiye tum login mein

Kriti Sharma 6 years, 1 month ago

Then tell some questions ishika

Amol Gùpta 6 years, 1 month ago

And abhi tkk mera physics and chemistry ka hi hua h jo aaj tha

Amol Gùpta 6 years, 1 month ago

He was asking questions regarding the project and related to the written practical we did that's it

ANSWER

About capacitor

Posted by Sumit Sharma 6 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Raunak Kumar 6 years, 1 month ago

It is an electric device which is used to store energy.

Jd Chouhan 6 years, 1 month ago

Godown of power

ANSWER

Cbse sample paper of 2018 - 2019

Posted by Ankita Ghosh 6 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

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