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What is transformer and types

Posted by Rajesh Yadav 5 years, 3 months ago

2 answers

A transformer is an electronic divice which is used to convert high AC voltage into low AC voltage and vise versa. Transformer are of two types:- 1- step-up transformer 2- step down transformer

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Devil ? 5 years, 3 months ago

Step down transformer and step down

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ANSWER

What is the biot-savart law???

Posted by _Joan_37 ... 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Shaina Choudhary 5 years, 3 months ago

This law deals with the the magnetic field or magnetic induction at a point due to a small current element. It is is also called as Laplace law

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Yogita Ingle 5 years, 3 months ago

BIOT-SAVART LAW:

We already know now that current carrying conductor generates magnetic field around themselves. Biot-Savart law just mathematically states the intensity of this magnetic field at a point.
According to the Biot-Savart law, magnetic field dBdue to current element idl, at a pointP situated at distancer from the current element idl,is:

i) directly proportional to the current element idl, ii) directly proportional to the sine of the angle (θ) between current element and r, and iii) inversely proportional to the square of the distance r between current element and the point

dB∝idl (sinθ)/r²

dB = (μ_o/4π)×idl×(sinθ)/r²

dB = idl × r / r³

1Thank You

... Yang ... 5 years, 3 months ago

Biot-Savart’s law is an equation that gives the magnetic field produced due to a current carrying segment. This segment is taken as a vector quantity known as the current element. HoPe It HeLpS yOu??

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ANSWER

Derive the expression for electric potential due to a dipole at an equatorial point.

Posted by Roshni Tamang 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Suryakant Swain 5 years, 3 months ago

At an equitorial point electric potential is zero

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A charge 2 macrocolumn is taken from infinity to a point in an Electric Field without changing its velocity. If work done against electrostatic force is -40 macro joule then the potential at the point is???

Posted by Roshni Tamang 5 years, 2 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What is th electric potential inside a charged shell of radius R. If the potential outside the shell is given by V=1/4pi epsilon not q/r. (r》> R)

Posted by Roshni Tamang 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

a long solenoid with 15 turns per cm has a long as a small loop of area 2.0 cm ^2 placed inside the solenoid normal to its axis. if the current carried by the solenoid changes steadily from 2.0 to 4.0 ampere in 0.1s what is the induced EMF in the loop while the current is changing?

Posted by Ragini Yadav??? 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

What are ohmic and non ohmic devices. Give example?

Posted by Afiya Shaikh 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Paras Jain 5 years, 3 months ago

Ohmic are those which follows ohm 's law and the graph of this is straight line . Non ohmic are those which does not follow ohm's law and the graph of this is not straight line.

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Aarya Pratap Singh 5 years, 3 months ago

Who follows the vector law of addition

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Tanya ?? 5 years, 3 months ago

Ohmic are those which obey ohm's law and non ohmic are not.....eg of ohmic are silver ,copper and non ohmic are semi conductors.

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ANSWER

Unit 2 sports and nutrition notes

Posted by Gagandeep Doad 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Tanya ?? 5 years, 3 months ago

I think u get from this app

2Thank You

ANSWER

What is the value of electric potential at an equitorial point?

Posted by Suryakant Swain 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 5 years, 3 months ago

(i) At axial points, the electric potential of a diople has maximum positive or negative value.
(ii) At equatorial points, the electric potential of a dipole is zero.

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There is 10 units of charge at the centre of a circle of radius 10m. The work done in moving 1m charge once around the circle will be: a.) Zero b.) 100 units c.) 10 units d.) 150 units Pls explain

Posted by K Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Suryakant Swain 5 years, 3 months ago

a. Zero

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Devil ? 5 years, 3 months ago

A) becoz equipotential surface .. but not sure...if anyone know rgt .. plz correct me.

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A 4 Meu C capacitor is charged to 400V and then the plates are joined through a resistor. Heat produced in resistor will be a.) 0.64J b.) 0.32J c.) 0.16J D.) 1.28J Pls answer?

Posted by K Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

find the interval in which the function f of X equal to X + 1 to the power 3 into x minus 3 to the power 3 is strictly increasing

Posted by Shibasis Khamari 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How to prepare for board from starting in 3 month?

Posted by Ankit Raj 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Usha Yadav 5 years, 3 months ago

If , you want to prepare yourself for Board Exam only in 3 months or 2 months For this you will have to study approximate 8 hours ......very effectively...... And you will have to make a prefect Timetable ..... With clearing the doubts .... you may forward.....

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Mishti ???? 5 years, 3 months ago

Dear, U have to see the marking scheme & previous year most asked topics to strengthen u'r prepration.. & It surely help u to prepare u well in few months... Regards.??

1Thank You

ANSWER

Write down the types of em waves and their uses

Posted by Ujjval Pareek 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Kirti Sharma? 5 years, 3 months ago

1.Radio waves-instant communication 2.Microwaves- data and heat 3.Infrared Waves- invisible heat 4.visible light rays-see the world around you 5. X-rays-pentrating radiation 6.Gamma rays- nuclear energy

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ANSWER

A particle of mass m and charge q is at the origin.Suddenly it is subjected to uniform electric and magnetic fields pointing along X direction.The particle will

Posted by Rishi Ranjan 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

conducting rod PQ of length 20 cm and resistance 0.1 ohm rests on two smooth parallel rails of negligible resistance AA' and CC'. It can slide on the rails and the arrangement is positioned between the poles of a permanent magnet producing uniform magnetic field B = 2.4 T. The rails, the road and the magnetic field are in three mutually perpendicular directions as shown in the figure. If the ends A and C of the rails are short circuited, find the (I) external force required to move the rod with uniform velocity v = 10 cm/s,

Posted by Vijaya Prajapati 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

State ampere law

Posted by Nishant Kumar 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Devil ? 5 years, 3 months ago

Mu not i = £B.dl

0Thank You

Yogita Ingle 5 years, 3 months ago

Ampere’s Law can be stated as: “The magnetic field created by an electric current is proportional to the size of that electric current with a constant of proportionality equal to the permeability of free space.”

1Thank You

Shweta? Dhama? 5 years, 3 months ago

It states that the line integral of magnetic field (Bvector) is around a closed path in vaccum is equal to myonot (u○) times the total current (I) threading the closed path...hope it helps u...

1Thank You

ANSWER

Which type of questions come in physics board

Posted by Bhavika Singh 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Mishti ???? 5 years, 3 months ago

Dear ,U can take help by PYQ's n with new sample papers it also show the pattern & format to you ... Regards. ??

2Thank You

Ankita ?? Arpita☺️ 5 years, 3 months ago

Previous year question dekhlo

5Thank You

ANSWER

What is the average value and r.m.s values??

Posted by Nisha Yadav 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Dhruv Kejriwal 5 years, 3 months ago

Rms is root mean square of all values but average means sum of all values divided by no. of values

0Thank You

Shweta? Dhama? 5 years, 3 months ago

0.607 I○(not)...

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Write principal, construction and working of metre bridge.

Posted by K Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Yang Yang 5 years, 3 months ago

Khushi??

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Meghna Thapar 5 years, 3 months ago

A meter bridge also called a slide wire bridge is an instrument that works on the principle of a Wheatstone bridge. A meter bridge is used in finding the unknown resistance of a conductor as that of in a Wheatstone bridge. It is the simplest practical application of the Wheatstone bridge that is used to measure an unknown resistance. Principle: Its working is based on the principle of Wheatstone bridge.

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ANSWER

Write the use of transformers in high tension power lines. What do you transformer? Explain.

Posted by K Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

A transformer is a passive electrical device that transfers electrical energy from one electrical ... Faraday's law of induction, discovered in 1831, describes the induced voltage effect in any coil due to a changing magnetic flux encircled by the coil. The piece of equipment that does this, humming with electromagnetic energy as it goes, is called a transformer.

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ANSWER

Frnds plz some one tell me which topics are removed from chapter 1 (electric charge and field) ??

Posted by Nisa Saini 5 years, 3 months ago

CBSE > Class 12 > Physics

4 answers

Shweta? Dhama? 5 years, 3 months ago

Removed topic is ?Electric field due to uniformly charged thin spherical shell & For more details u can check out ?on Google...

1Thank You

Ragini Yadav??? 5 years, 3 months ago

Field due to uniformly charge thin spherical cell is removed

1Thank You

Devil ? 5 years, 3 months ago

Ef of hollow sphere , solid sphere

2Thank You

Gautam Kumar 5 years, 3 months ago

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ANSWER

Define gauss theorem and its application ....in easy language plz ????

Posted by Nisa Saini 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Suryakant Swain 5 years, 3 months ago

The law states that- "The net electric flux enclosed by a closed surface is 1/E' times of the total charge of that surface"...

0Thank You

Dhruv Kejriwal 5 years, 3 months ago

The flux is given by q(inside the surface )/absalanot

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Shweta? Dhama? 5 years, 3 months ago

According to gauss theorem the total flux through a closed surface is 1/f silion not times then the net charge is enclosed by the closed surface.... Their r 4 Application of gauss theorem...

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ANSWER

Motion of charged partical in magnetic and electric field ?

Posted by Archana Yadav 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Dhruv Kejriwal 5 years, 3 months ago

It's of 2 type helix with increasing pitch when E and B are parallel and perpendicular to velocity And Straight line when E and B are Perpendicular to each other and velocity

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ANSWER

Physics board me numericals ki weightage kitni hoti h?

Posted by Bhavika Singh 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Bhavika Singh 5 years ago

Oh yeah?

0Thank You

Mishti ???? 5 years, 3 months ago

Dear bhavika, Frankly speaking as such their is no guideline for numerical but if you see the trend then maximum 15 marks numerical they r asking. You can prepare numerical from the following chapters. Electrostatics: gauss law Current electricity: wheatstone bridge, potentiometer,KVL loop… MAGNETIC effect of current: galvanometer….ammeter and voltmeter conversion EMI And AC: LCR circuit impedance numerical Optics: lens makers formula Dual nature: debroglie wavelength Atom and nuclei: Bohr's model, spectral lines Or for more u can take a idea from Previous year board papers nd by our new sample papers.... Regards. ??

2Thank You

Mishti ???? 5 years, 3 months ago

??? nice sense of humor dear Yang...

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Bhavika Singh 5 years, 3 months ago

Chal

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... Yang ... 5 years, 3 months ago

I think 10kg hoga???

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ANSWER

When the exam of board 2021 held?