Incorrect URL accessed!!!!

ANSWER

Will questions come from sample papers of mycbse guide for 2018 physics board exam

Posted by Vismaya Raman 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Ankita Vats 8 years, 1 month ago

Approx same as last years

ANSWER

What is krichoffs rule

Posted by Richa Bharti 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Kalindi Yadav 8 years, 1 month ago

Kirchhoff's first rule—the junction rule. The sum of all currents entering a junction must equal the sum of all currents leaving the junction. Kirchhoff's second rule—the loop rule. The algebraic sum of changes in potential around any closed circuit path (loop) must be zero.

Deep Patel 8 years, 1 month ago

Please refer ncert text book part 1

Birendra Pattnaik 8 years, 1 month ago

KCL-acc. to law the algebraic sum of the current meeting at a juction is 0 or constant.

ANSWER

What will happen if fields were not uniform?

Posted by Divya Sharma 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Nsb Bz 8 years, 1 month ago

The force will not be zero. Force and torque both will act on dipole.

ANSWER

A passer in aeroplane can see a rainbow

Posted by Aditya Singh 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Saurabh Kumar 8 years, 1 month ago

yes.... offcourse..but.. the sun should be at 180 degrees from your postion ...

Vikash Kumar 8 years, 1 month ago

yes

ANSWER

What is the function of radial magnetic field in the moving coil galvanometre?

Posted by Lekha Raj 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Ankita Vats 8 years, 1 month ago

It works in magnetise and demagnetise of particle which also increase its speed.

Kalindi Yadav 8 years, 1 month ago

Sorry, It's not sin there it's sin theta.

Kalindi Yadav 8 years, 1 month ago

Radial MF in moving coil galvanometer is to get maximum torque in all directions. Torque=BINA sin there Because of Radial MF theta is 90 and sin 90° is 1. Hence, Torque is maximum BINA.

ANSWER

Phase relation amplifier

Posted by Anmol Kumar 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is tha paper type in 2018

Posted by Darshit Sharma 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

A convex lens and a convex mirror (of radius of curvature 20cm)are placed coaxially with the convex mirror placed at a distance of 30cm from the lens. For a point object placed at a distance of 25cm from the lens, the final image due to this combination coincides with the object itself. Find the focal length of convex lens and convex mirror.

Posted by Manan Ahuja 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Is additional exercise important

Posted by Abhishek Soni 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Priya Prakash S 8 years, 1 month ago

Not important

Deep Patel 8 years, 1 month ago

It is as a diamond in a pit of coal

Lekha Raj 8 years, 1 month ago

ANSWER

Is nicol prism in cbse syllabus.....

Posted by Deep Malik 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Rishabh Srivastava 8 years, 1 month ago

ANSWER

Define drift velocity and drive an expression for it.

Posted by Rumi Ansari 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

Dreift velocity is the velocity attained by any particle such as electron when kept in an electric field. Derivation: Consider a cross section of conductor with length ‘l’ and area ‘A’. Let n be the no of electrons per unit volume. The volume of conductor can be given as V = Al No. of electrons=nAl Charge, q = ne= neAl When connected with a battery current I pass through it which is equal to, I = q/t=neAl/ t Since,l/t=Vd we can write this equation as: I= enAVd

ANSWER

Capacitor ki polarity kaise dekhege Agr loop mein current clockwise or anticlockwise dono direction mein current move kr rha h toh

Posted by Hina Siddiqui 8 years, 1 month ago

CBSE > Class 12 > Physics

6 answers

Hina Siddiqui 8 years, 1 month ago

Plate A & B ki polarity bhi bta do?????..

Kanak Tiwari 8 years, 1 month ago

Sorry bt instead of by

Kanak Tiwari 8 years, 1 month ago

Actually I was asking are you a topper of class to Garima by I didn't put question mark and estimate it wrong

Lekha Raj 8 years, 1 month ago

Are you a topper of Garima's class? Sahi sentence..........kya kroge eng m

Kanak Tiwari 8 years, 1 month ago

Is you are a topper of the class Garima

Kalindi Yadav 8 years, 1 month ago

The direction of induced current when seen from the left hand side is Anticlockwise, and its direction is Clockwise when seen from right hand side.

ANSWER

Dimensions of resistivity?

Posted by Divakar Nain 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

[ρ] = [ML²T-³A-²][L] = [ML³T-³A-²]

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Why electrones cannot be accelerated in a cyclotron

Posted by Aman Narain 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Ankita Vats 8 years, 1 month ago

Because it's mass increase with increase in speed.

Kalindi Yadav 8 years, 1 month ago

1. A cyclotron cannot be used to accelerate electrons because electrons are of very small mass. Thus, the velocity will be increased to such a great extent that the electron will be thrown out of the step with the oscillating field.

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Find the energy equivalent of one atomic mass unit,first in joules and then in MeV.using this, express the mass defect of O in MeV/c^2

Posted by Zala Heenaba 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

1 amu=1.66×1027 kg C= speed of light = 3×108 m/s E = mc² E= 1.66×1027×( 3×108)² E = 1.49×10−10 joule 1 MeV= 1.6×10−13 J E = 1.49×10−10/1.6×10−13= 931.6 MeV In O,mass no = 16 energy for 16 amu = 16×931.6 = 14905.6 MeV mass defect = energy/c²= 14905.6 MeV/c²

ANSWER

What is global positioning system ? Explain it's working principle in brief

Posted by Harsh Chauhan 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Prerna Pahwa 8 years, 1 month ago

GPS is method to locate the position of any place,buildings,etc.on earth by using em waves and satellite system. The satellite system uses a set of 24satellitewhich are continuously orbiting and mapping the surface of the earth.the orbit of these satellite are so arranged that at least 4 satellite are looking a place on surface of earth . GPS device is fitted in system .when the user of system wants to locate the exact position of place on the earth,he feed it to system. This system transmit and receive em wave and get linked up with satellites As a result longitudinal coordinates of desired place is determine by determining its distance with at least 3 satellites. The information is processed further to identified the unique location of desired place

Kalindi Yadav 8 years, 1 month ago

A GPS receiver shows where it is. It may also show how fast it is moving, which direction it is going, how high it is, and maybe how fast it is going up or down. Many GPS receivers have information about places. GPSs for automobiles have travel data like road maps, hotels, restaurants, and service stations. GPSs for boats contain nautical charts of harbors, marinas, shallow water, rocks, and waterways. Other GPS receivers are made for air navigation, hiking and backpacking, bicycling, or many other activities. The majority are in smartphones.

Kalindi Yadav 8 years, 1 month ago

A Global Positioning System, also known as GPS, is a system designed to help navigate on the Earth, in the air, and on water.

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Drive lens formula

Posted by Gyanesh Dubey 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

State biot savrat's law and apply it to find the magnetic field at a point due to long straight conductor carrying current

Posted by Altifa Khanushiya 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

The magnetic field produced by a current carrying element of length dl, carrying current I at a point separated by a distance r is given by dB = μo / 4 π Idl * r / r3 or dB = μo / 4 π Idl sin θ / r2 where, θ is the angle between the direction of the current and μo is absolute permeability of the free space. SI unit of magnetic field is Wm-2 or (tesla) and CGS unit of magnetic field is gauss or oersted 1 gauss = 10-4tesla.

ANSWER

Why electric field line never intersect with each other

Posted by Naman Sahu 8 years, 1 month ago

CBSE > Class 12 > Physics

4 answers

Divakar Nain 8 years, 1 month ago

It cannot be possible because the point which is present at that intersect point cannot have resultant direction in two different direction

Mahima Kumari 8 years, 1 month ago

because they all are in same direction

Saurabh Kumar 8 years, 1 month ago

because if they intersect, at the point of intersection there will be two direction for positive charge to move on at the same time.... and that is not possible... thats the reason...

Amaljith J D 8 years, 1 month ago

Bcz..at point of intersection it would mean that, the point has two direction of MF which is not possible. So the MF line never intersect.

ANSWER

is photo cell of dual nature of radiation chapter in syllabus?

Posted by Saurabh Kumar 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Aditya Raj 8 years, 1 month ago

Yes

ANSWER

Derivation for mirror equation?

Posted by Gopika Malu 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

Refer Ncert text book of class -12 part _II Page No. 312,313 and 314.

ANSWER

Derive torque on a bar magnet in uniform magnetic field

Posted by Shikha Rai 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Deep Patel 8 years, 1 month ago

Refer ncert

ANSWER

Explain about moving coil galvanometer??

Posted by Sulekha Mawase 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

Principle: The working of moving coil galvanometer is that when a current carrying coil is placed in a varying magnetic field, it experiences torque.

ANSWER

What is the principle of cyclotrone

Posted by Aryan Agrawal 8 years, 1 month ago

CBSE > Class 12 > Physics

3 answers

Shikha Rai 8 years, 1 month ago

Its principle based on when charge particle on exerting electric force and magnetic force perpendicular to each other it accelerate and move along a circular path of larger radii which finally comes out from a window and stricks the target.

Kalindi Yadav 8 years, 1 month ago

The working of cyclotron is based on the fact that a positively charged particle can be accelerated to a sufficiently high energy with the help of smaller values of oscillating electric field by making it to cross the same electric field time and again,with the use of strong magnetic field.

Jin Kazama 8 years, 1 month ago

Heavy +ve charges can be acc. to high speed

ANSWER

Van de graaff

Posted by Tushar Chander 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Jin Kazama 8 years, 1 month ago

Not in syllabus

ANSWER

Drive an expression for the electric field at a point on the axial line?

Posted by Abhishek Dubey 8 years, 1 month ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How are xrays produced?

Posted by Asif Jain 8 years, 1 month ago

CBSE > Class 12 > Physics

2 answers

Prerna Pahwa 8 years, 1 month ago

Inner shell electron Sudden deceleration of fast moving electron by a metal target

Yuthika Yadav 8 years, 1 month ago

When fast moving electron hit a heavy metal target

ANSWER

Please anyone tell me kya y=acoswt+theta ko y= acoswtsintheta+asinwtcostheta likh sakte hai kya

Posted by Yuthika Yadav 8 years, 1 month ago

CBSE > Class 12 > Physics

1 answers

Kalindi Yadav 8 years, 1 month ago

No.Becuse Y= a cos(wt+ϕ) can be written as a( coswt cos ϕ- sin wt sin ϕ). Since cos(A+B)=cos A cos B - sin A sin B. But,Y=a sin(wt+ϕ) can be written as Y= a(sin wt cos ϕ + cos wt sin ϕ).Because sin (A+B)= sin A cos B + cos A sin B.