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What is null point ?

Posted by Maneet Singh 7 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Akash Seth 7 years, 4 months ago

at that point where current is 0 that point is called null point

0Thank You

Kalpna B. K. 7 years, 4 months ago

When the field quantity is zero that means galvanometer shows no deflection

0Thank You

ANSWER

A coil is wrapped on conducting frame in galvanometer.Why??

Posted by Shikhar Kasaudhan 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Chirag Solanki 7 years, 4 months ago

coil wound on soft iron frame but elecrically coil not in contact with frame

there are two reason

1 to get radial magnetic field

2 all magnetic field line link with coil

0Thank You

ANSWER

Tell me about the electric flux?

Posted by Ravi P S 7 years, 4 months ago

CBSE > Class 12 > Physics

3 answers

Akash Seth 7 years, 4 months ago

the surface integral of electric field is called electric field that is the number of electric line of field passing through normally to the surface is called electric flux by mathematically the dot product of electric field and surface area is called electric flux

1Thank You

Shiva Tiwari 7 years, 4 months ago

The total no of magnetic field lines passing through the closed surface normally . It is denoted by phi suffix me B . Its SI unit is WEBER

2Thank You

Rohit Singh 7 years, 4 months ago

The total no. of magnetic field lines passing through a unit area is called magnetic flux.

3Thank You

ANSWER

Derivie the eqution for common potential

Posted by Jagmohan Singh 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Sambhav Sabharwal 7 years, 4 months ago

see ncert

0Thank You

ANSWER

Why focal length is always negative in concave mirror?

Posted by Adesh Chahar 7 years, 4 months ago

CBSE > Class 12 > Physics

4 answers

Muskan Verma 7 years, 4 months ago

Focal length is always negetive in concave mirror because reflection process takes place on smooth surface and its smooth surface lies on left side therefore all parameters like f n u are taken as negative

0Thank You

Abhineet Aanand 7 years, 4 months ago

It's acc to sign convention

0Thank You

M. पी. Rai 7 years, 4 months ago

Inconcave mirror always focal length is zero because it's image form left side

0Thank You

Manvi Dhariyal 7 years, 4 months ago

Focal length is always positive for concave mirror. It is negative for convex mirror.

0Thank You

ANSWER

why emf is greater than internal resistance?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Vinayak Raghuvanshi 7 years, 4 months ago

becacuse emf is a type of potential difference which make the charge to flow

0Thank You

ANSWER

Bhor magnetron ?

Posted by Devashish Sharma 7 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How to solve kq4e/x2=kqe/a-x2

Posted by Roshni Singh 7 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

Distinguish between the magnetic property of Dia fero paramagnetic substance in term of (1)suceptiblity (2)permablity (3)coercivity

Posted by Himanshu Yadav 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Manvik Malhotra 7 years, 4 months ago

Read pradeep book surely you get answer?

0Thank You

ANSWER

Should resistance can be negative?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Siva Dasan 7 years, 4 months ago

Why

0Thank You

Manan Bedi 7 years, 4 months ago

3Thank You

ANSWER

Should resistivity can be negative?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

should potential difference can be -ve?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Mohit Sepat 7 years, 4 months ago

In which condition it is negative

0Thank You

Ishita Gupta 7 years, 4 months ago

Yes

1Thank You

ANSWER

How to solve (R2R3) +R1?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Manvik Malhotra 7 years, 4 months ago

Try yourself again it so easy if you cannot we will help

0Thank You

ANSWER

In parallel connection V1, V2 is not taken, but in series V1, V2 is taken. Why is it so?

Posted by Siva Dasan 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Manan Bedi 7 years, 4 months ago

Because in parallel combination V is constant whereas in series,V is not constant

1Thank You

ANSWER

ExplAin the drift velocity.?

Posted by Monťý Harsh 7 years, 4 months ago

CBSE > Class 12 > Physics

3 answers

Rohit Singh 7 years, 4 months ago

It is the average velicity of an electron when it drift toward the +ve terminal of battery under the applied external field.

1Thank You

Kundan Singh 7 years, 4 months ago

Drift velocity is the average velocity gain by free electrons.

0Thank You

Shubham Thakur 7 years, 4 months ago

Drift velocity is that average velocity with which free electrons of the conductor drifted from one end to other end.

0Thank You

ANSWER

A source of AC circuit contains inductance 20mH a capacitance 100 microfarad a resistance 50 ohm an AC source of 12 V , 50 Hz. Find the energy dissipated in the circuit In 1000 sec

Posted by Tannu Yadav 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Vaibhav Gaur 7 years, 4 months ago

3Thank You

ANSWER

The resistivity of copper is 1.7×10-8 ohm and that of aluminium is 2.7×10-8 ohm which material is preferred to use for transmission of electric power and why ?

Posted by Thejaswini Chirnalli Mattad 5 years, 8 months ago

CBSE > Class 12 > Physics

3 answers

Thejaswini Chirnalli Mattad 7 years, 4 months ago

Please send answer for question and it is three mark question

0Thank You

Thejaswini Chirnalli Mattad 7 years, 4 months ago

I want this answer for 3 marks question

0Thank You

Vijay Dwivedi 7 years, 4 months ago

Copper because less resistivity means less resistance can flow more current in constant voltage

1Thank You

ANSWER

Will there be any current induced in the coil shown in fig

Posted by Nitin Tomar 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Riya Gupta 7 years, 4 months ago

Where is the figure

0Thank You

ANSWER

Why the surface of moving coil galvanometer is cylindrical

Posted by Swarnava Ghosh 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Vijay Dwivedi 7 years, 4 months ago

To give the radial magnetic field

1Thank You

ANSWER

How we can score good marks in phys and in its numerical specially

Posted by Manjot Gill 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Shivanshu Pal 7 years, 4 months ago

By practising more and more.

1Thank You

ANSWER

Which one of the two , an ammeter or a miliammeter , has higher resistance and why ??

Posted by Neha Yadav 7 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

Harshrajsinh Zala 7 years, 4 months ago

Its ammeter

0Thank You

Divyanshu Sahu 7 years, 4 months ago

Offcourse miliameter yar........

2Thank You

ANSWER

Why a rest charge does not experience any force.

Posted by Shivam Rai 5 years, 8 months ago

CBSE > Class 12 > Physics

1 answers

Manan Bedi 7 years, 4 months ago

Bcz a rest charge has no velocity and force=qvb

0Thank You

ANSWER

Concept of paeallel and series combination

Posted by Chandan Kumar 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Aayush Kumar 7 years, 4 months ago

These combinations allows us to generate the accurate values of resistance , capacitance etc. , which can not be obtained by just a single circuit element , such as resistor, capacitor etc.

0Thank You

ANSWER

calculate the electric field due to an electric dipole of long 10cm constitute of charge of 100 columb at a point 20cm away from the charge ?

Posted by Amania Rilo 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Saurabh Kumar 7 years, 4 months ago

277890000000000000NperC

3Thank You

ANSWER

How to Study at Night (if feeling sleepy)??????

Posted by Nitish Sharma 7 years, 4 months ago

CBSE > Class 12 > Physics

5 answers

Nitish Sharma 7 years, 4 months ago

THANK YOU GUYS I APPERICIATE ALL YOUR ADVICES☺️☺️????????

1Thank You

G K 7 years, 4 months ago

When u feel sleepy...??... then do something which u like or feel happy...?....for ex.- if u like dance then start dancing....u can also read some short stories books....u can also hear music.....OR IT'S NOT IMPORTANT KI FULL NIGHT PADHNA HI JRURI H. ...when u feel sleepy go to sleep and sleep atleast 6-7 hrs.......then wake up in early morning ?...and start studying......AND IF U ALSO FEEL SLEEPY IN MORNING TO BHAII YE TO CHINTA KA VISAY H.....

2Thank You

Eshaan Gupta 7 years, 4 months ago

Watch a movitational video...

2Thank You

Md Tauseef Khan 7 years, 4 months ago

Think about your future

1Thank You

Anjana Sherawat 7 years, 4 months ago

Think about your goal

6Thank You

ANSWER

If a chid fails in first attempt of class 10 compartment can get admission in class 11

Posted by Satyam Tiwari 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Manhar Singh 7 years, 4 months ago

1Thank You

ANSWER

An alternating voltage given by V=110 sin314t is connected across a pure resistance of 50 Ω, Find the frequency of the source and rms current through the resistance.

Posted by Jagriti Shrey 7 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

H!Mαη$Hμ Ұαδαυ ✔️ 7 years, 4 months ago

It is easy .... Omega =314 rad/s..... _f=314/2π _f=314/2*3.14 _f=50 Hz........ ........and I rms =V rms /R... I rms =110/50 ... I rms=11/5.... I rms=2.2 A

1Thank You

ANSWER

Two charges ,of 5nC and -2 nC ,are placed at point (5 cm,0,0) and (23 cm,0,0)in a region of space where ,there is no other field .Calculate the electrostatic potential energy of this charge system.

Posted by Ashu Tosh 7 years, 4 months ago

CBSE > Class 12 > Physics

3 answers

Nitish Sharma 7 years, 4 months ago

0.5 x10-7

0Thank You

G K 7 years, 4 months ago

Camera ka option bhi hona chahiya tha.....so that I can send u my solution....?

1Thank You

G K 7 years, 4 months ago

-5×10^-7 J.....or simply 0.5microJ.....

0Thank You

ANSWER

Parallel plato capacity

Posted by Akhilesh Yadav 7 years, 4 months ago

CBSE > Class 12 > Physics

2 answers

G K 7 years, 4 months ago

Parallel Plate Capacitors are the type of capacitors which are formed by arrangement of electrodes and insulating material (dielectric) The two conducting plates act as electrodes which are separated by a dielectric between them. The two plates of parallel plate capacitor are of equal dimensions and is connected to power supply. The plate which is connected to positive terminal of battery acquires positive charge while the plate which is connected to negative terminal of battery acquires negative charge. Due to the attraction charges store between the plates

2Thank You

G K 7 years, 4 months ago

U mean......parallel plate capacitor.....

0Thank You

ANSWER

What is laser

Posted by Neha Kumari 7 years, 4 months ago

CBSE > Class 12 > Physics