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Two particles having ( a & p) equal k.E. what is the ratio of wavelength?

Posted by Prachi Sahu 7 years ago

1 answers

Acc to de broglie , Wavelength = h/p where p is momentum of particle Also , p = √2KE.M Now h is constant , M is constant and also K.E. have equal values which means KE will also be constant So the required ratio would be Mass of b/ Mass of a

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Is all numerical of ncert is necessary to do

Posted by Rahul Pandey 7 years ago

CBSE > Class 12 > Physics

1 answers

Ashwini Kumar Mohanty 7 years ago

the same type of questions come in the exam with the values are changed

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Why we use step down transformer in rectifiers

Posted by Nïßhåñt Bhàrdwàj 7 years ago

CBSE > Class 12 > Physics

1 answers

Mahaalakshmi Vijayamoorthy 7 years ago

Because large voltage might damage the diode permanently.

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What are the important questions from chp-4,5,6,7

Posted by Kartheek Chowdary Vattkuti 7 years ago

CBSE > Class 12 > Physics

0 answers

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An electric dipole with dipole moment 24 multiple by 10 raise to -2 alligned at an angle of 30• where the electric field uniform of magnetude 15 multiple by 10 raise to power 4 Nl calculate torque

Posted by Nazneen Khan 7 years ago

CBSE > Class 12 > Physics

1 answers

Sayeda Iram Ateeq 7 years ago

T=pEsin0 (theeta) Given: p=24×10^-2 E=15×10^4 & 0=30° Now, T=24×10^-2×15×10^4×sin30° 'T=18×10^3 Nm'

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Relating b/w relaxayion time&curret desity

Posted by Rahul Singh 7 years ago

CBSE > Class 12 > Physics

1 answers

H I T E S H 7 years ago

Let the volume of conductor =A*l No. Density of electrons =n Total no. of electron in conductor =nAl Charge on electron=e Total charge of all electrons in conductor =q=nAle I=q/t=nAle/t------(1) We know velocity =displacement/time Velocity =l(lengthof conductor) /time Time=l/velocity t=l/Vd Putting value of t in equation (1) I=nAleVd/l I=nAeVd-----(2) We know Vd=eET/m Putting in equation (2) I=nAe2ET/m

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Relation b/w avg value and peak value of ac

Posted by Himanshu Sadana 7 years ago

CBSE > Class 12 > Physics

0 answers

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Is potential difference scalar or vector

Posted by Dev Mavi 7 years ago

CBSE > Class 12 > Physics

2 answers

Pooja Bhatia 7 years ago

Scalor

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Sayeda Iram Ateeq 7 years ago

Vector!

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Flux nikalte samay negative sign nahi lagate ?

Posted by Ambuj Mishra?? 7 years ago

CBSE > Class 12 > Physics

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Realation between averagee value and peak value of ac

Posted by Himanshu Sadana 7 years ago

CBSE > Class 12 > Physics

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Is it enough for board paper of phy to solve sample papers that cbse provides with last 5yrs question papers?

Posted by Anagha Shete 7 years ago

CBSE > Class 12 > Physics

1 answers

Shriya Gautam 7 years ago

Nothing can be said physics is already too confusing don't take risk read out every once formulas

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What is the cause if conduction current

Posted by Mehhul Garg 7 years ago

CBSE > Class 12 > Physics

1 answers

Prajjawal Sharma 7 years ago

conduction current is within conductor so movement of e is cause

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Where i found previous year question paper withiut solution ?

Posted by Harsh Gautam 7 years ago

CBSE > Class 12 > Physics

0 answers

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List of topics which are deleted from the chapter ray optics

Posted by Aryan Sihag 7 years ago

CBSE > Class 12 > Physics

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Does the magnifying power of microscope depend upon the colour of light used? Justify.

Posted by Aryan Sihag 7 years ago

CBSE > Class 12 > Physics

1 answers

Shifali Bijily 7 years ago

No. It just depends on focal lengths of the lenses Since, m= -L/fo × (1+D/fe)

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What r the important chapters which I learn. I can get good marks... Very important chapters

Posted by Shashwat Nigam 7 years ago

CBSE > Class 12 > Physics

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Relation between half life and decay contact

Posted by Momena Momtaz 7 years ago

CBSE > Class 12 > Physics

2 answers

Sayeda Iram Ateeq 7 years ago

Decay constant=0.693/half life

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Raghav Ojha 7 years ago

There is inverse relation between them T

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What is mean by invisible? Is it mean that a invisible partical, which is don't exist

Posted by Akash Seth 7 years ago

CBSE > Class 12 > Physics

2 answers

Prajjawal Sharma 7 years ago

Invisible means light is not reflected from the body to reach our eyes it simply passes undeflected as refractive index of body and surrounding is same

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Mohit Kumar 7 years ago

Yes, the indivual means the partical which are doesn't exits in the environment

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Is Davison germer experiment in our syllabus

Posted by Divyansh Rathore 7 years ago

CBSE > Class 12 > Physics

1 answers

Sayeda Iram Ateeq 7 years ago

Yup!

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How we are prepare for passing marks

Posted by Priyanshu Rajput 7 years ago

CBSE > Class 12 > Physics

1 answers

Priyanshu Rajput 7 years ago

Reading physics carefully

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Gauge theorem

Posted by Caslin Khongsai 7 years ago

CBSE > Class 12 > Physics

1 answers

Nikhil Sharma 7 years ago

This law states that the magnetic flux linked with any hypothetical surface of any shape is equals to the one upon epsilon times the net current enclosed within the curve.

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Is feedback amplifier is in syllabus?

Posted by Shreya Singh 7 years ago

CBSE > Class 12 > Physics

1 answers

Riya Singhal 7 years ago

No its not in syllabus

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Does full wave rectifier work on forward and reverse bias?

Posted by ....... ........ 7 years ago

CBSE > Class 12 > Physics

1 answers

Manish Yadav 7 years ago

yes firstly the diode (D1)WAS forward baised and diode (D2 ) IN REverse bais

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State the SI unit of electic polarisation vector p

Posted by Piyush Yadav 7 years ago

CBSE > Class 12 > Physics

1 answers

Himanshu Rock 7 years ago

Coulomb per meter square??

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Important topics in physics

Posted by Nishat Shabnam 7 years ago

CBSE > Class 12 > Physics

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Define self inductance of a coil. Show that magnetic energy required building up the current I in a coil of a self inductance L is given by 1 upon 2 l i square

Posted by Nishat Shabnam 7 years ago

CBSE > Class 12 > Physics

1 answers

Manish Singh 7 years ago

Self-inductance of a coil is numerically equal to the magnetic flux linked with the coil when the current through coil is one Ampere. The energy req dW/dq=L dI/dt dW=L dq/dt *dI dW=L I dI On integrating W=L sq(I)/2 which is energy

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What is meant by saturation or cutoff transistor

Posted by Manish Singh 7 years ago

CBSE > Class 12 > Physics

1 answers

Manish Singh 7 years ago

In cutoff condition emitter current is zero and the collector current consists of small reverse saturation currents. The transistor when used as switch is operated in cutoff on condition and saturation regions which corresponds to switch off an on condition respectively.

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A 20 microfarad capictor is charged by 30 V DC supply and then connected to an uncharged 50microfarad capacitor. Calculate initial and final energy. Find potential difference across the combination.

Posted by Gagandeep Kaur Punia 7 years ago

CBSE > Class 12 > Physics