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What is permittivity?

Posted by Aashka Jain 5 years, 3 months ago

2 answers

Sahil Kumar 5 years, 3 months ago

It is defined as the ability of the medium to pass the electric line of force, defines the term "permitivity". It is represented as :-- (latex software) \in = (\in_0)(\in_r) or \int_0 = \dfrac{\in}{\in_r}.

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Shubham Dahiya 5 years, 3 months ago

The ability of a substance to store electrical energy in an electric field

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A capacitor of 200 pf is charged by a 300v battery

Posted by Aanchal Agrahari 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Harshit Jain 5 years, 3 months ago

Apply Q=cv

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Conceptual question: A charge has mass 9.11×10^-19c is travel with the half velocity of light (c/2) then what is its charge??????JEE/ADV.

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Shivam Yadav 5 years, 3 months ago

+ve ?

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What is conservation of charge?? Can charge created or destroyed.?. IITJEE /ADV.

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

Vicky Shukla 5 years, 3 months ago

Charge can created and also destroyed But net electric charge is 0( zero ) Because elecric charge is an isolated system ( Thankyou) ???

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Neha Pandey 5 years, 3 months ago

According to this ,for an isolated system net charges always remain constant Charge can never be created nor destroy but it can be transferred to one object to another object

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Meghna Thapar 5 years, 3 months ago

In physics, charge conservation is the principle that the total electric charge in an isolated system never changes. The net quantity of electric charge, the amount of positive charge minus the amount of negative charge in the universe, is always conserved. The law of conservation of electric charge states that the net electric charge of an isolated system remains constant throughout any process. In simple words, charge can neither be created nor destroyed. Because of certain symmetries in the structure of the universe, the total electric charge of an isolated system is always conserved. This means that the total charge of an isolated system is the same at all points in time. The Law of Conservation of Charge is a fundamental, strict, universal law. The only thing that has changed is that they have given up a little bit of their energy. This happens because electrons are charged and the total amount of charge is always conserved. Because charge is always conserved, you can determine exactly how current must flow in each branch of a circuit.

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Alpha decay explain with ex

Posted by Medhini G.S 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Sahil Kumar 5 years, 3 months ago

Alpha decay is a part of Radioactivity disintegration. As you know, (Alpha, beta, gamma) rays are originated from Radioactivity. Definition of Alpha Decay- When any Alpha particle is emitted from any source then it's number of protons (Atomic Number) is decreased by 2 unit, and there is no any further change in their mass number(A). For an example:-- Uranium(Z=92,A=238) decay into---------- Thallium (Z=90,A=234) + Helium (Z=2,A=4). Or Metal A (Z,A) decays---- Metal A (Z--2, A).

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Expression for half life of radioactive nuclide

Posted by Medhini G.S 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

The half life of radioactive nuclides is defined as the time in which half of the original number of radioactive atoms has decayed. Example: Imagine you start with 100 atoms of nuclide X. X decays to nuclide Y with a half life of 10 days. However, the half-life can be calculated from the decay constant as follows: half-life = ln (2) / (decay constant). To measure the decay constant, we take a sample of known mass and measure the number of radioactive decays per second as a function of time.

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Is induced current an essential consequence of induced emf in all situations

Posted by Aryan Agrawal 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

? ? 5 years, 3 months ago

Only if the circuit is closed....if the circuit is not closed then induced emf will not generate current

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What is a magnetic dipole?How can we find its direction?

Posted by Rohit Krishna 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 5 years, 3 months ago

The magnetic dipole moment of the current loop is equal to the product of ampere-turns and area of current loop. It is denoted by M.

M = nIA

Where, n = number of turns in a circular current loop.

I = current through the loop.

A = area of each turn of the loop.

Magnetic dipole moment is a vector quantity. Its direction is perpendicular to the plane of loop outwards for anticlockwise current in loop and is directed inwards for clockwise current in loop.

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capacitor with C=4 µF is charged by a 2V battery. The battery is removed after the capacitor is fully charged. A second capacitor 2 µF is now connected to complete the circuit. (i). What is the final charge on each capacitor? (ii). What is the final Energy on each capacitor?

Posted by Madesh C 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

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how should we prepare for boards

Posted by Shalu Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Tanvi Sharma 5 years, 3 months ago

With the help of study

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How current is able to pass when the potential difference is 0 at two different points of the same side of conductor?

Posted by Sree Ramana 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Krishna 5 years, 3 months ago

Note the point that potential difference is required at the ends of a conductor "WITH A RESISTANCE" for current to flow.If the conductor has zero resistance,current will naturally flow through it in the absence of potential difference.In the case of a zero resistance conductor,current through it will be infinity( as current always follows low resistance path) ........

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What is presure

Posted by Mandeep Kaur 5 years, 3 months ago

CBSE > Class 12 > Physics

5 answers

Ranjit Singh 5 years, 3 months ago

Force by area

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? ? 5 years, 3 months ago

F/A

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Manoj Thakur 5 years, 3 months ago

Force by area

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Shruti Singh 5 years, 3 months ago

Pressure is force acting per unit area.

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Rohit Krishna 5 years, 3 months ago

Force acting on a surface per unit area is called pressure.Its SI unit is N/m^2 or pascal(Pa)

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What is a eletric charge

Posted by Vinay Vinay 5 years, 3 months ago

CBSE > Class 12 > Physics

2 answers

Hunnar Khurana 5 years, 3 months ago

Electric Charge is intrinsic property of matter which gives rise to current in a partucular time

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? ? 5 years, 3 months ago

Electric charge is a property of material due to which it is able to move its electrons to generate current with respect to time. Electric charge is represented by 'q' and q=it where i is current and t is time.

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calculate energy stored in capacitor of 10uf of charged to 20v

Posted by Yuvraj Kumar 5 years, 3 months ago

CBSE > Class 12 > Physics

3 answers

? ? 5 years, 3 months ago

2*10^-3 rohit's method is absolutely correct

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Rohit Krishna 5 years, 3 months ago

Sorry you should take 20^2= 400 Hence answer will be 1/2 * 10 * 10^-6 * 20 *20= 2 * 10^-3 J ...

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Rohit Krishna 5 years, 3 months ago

Use the formula Energy,U=1/2*c*V^2, • where c is the capacitance in SI units and V is the potential difference in SI units . Hence, U=1/2* 10* 10^-6 * 20 = 10^-4 J. (10uF= 10* 10^-6 F) I hope this is the answer...

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What is equivalent distance in vacuum???? IIT jee /adv.

Posted by Ayush Vishwakarma?? 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Gaurav Seth 5 years, 3 months ago

The equivalent distance in vacuum due to the introduction of dielectric is x√k. The net distance between the charges is r – x - x√k.

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What is magnetic field of circular coil

Posted by Manoj Anuragi 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Yogita Ingle 5 years, 3 months ago

At the centre of the circular loop, The magnetic field lines are straight. Each segment of circular loop carrying current produces magnetic field lines in the same direction with in the loop. The direction of magnetic field at the centre of circular coil is perpendicular to the place of the coil.

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Radius of current carrying coil is 'R'.Then ratio of magnetic fields at the centre of the coil to the axial point which is R/root 3 distance away from the centre of the coil :-

Posted by Devansh D 5 years, 3 months ago

CBSE > Class 12 > Physics

0 answers

ANSWER

How to calculate the force on a charge where there are not one but several charges around?

Posted by Priyansh Sharma 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Krishna 5 years, 3 months ago

Use superposition principle to calculate the vector sum of all the forces acting on a single charge due to multiple charges.

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Why it is safer to sit inside a car during a thunderstrom?

Posted by Manoj Kumar 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

Rohit Krishna 5 years, 3 months ago

The car is usually an automobile made up of metal.And as we know,metals are good conductors.So they conduct electricity and also note that charge on a conductor is always concentrated on its surface(distributed all over).Hence the field inside a conductor is zero.This is known by the term electrostatic shielding.As the car is made of metal,the field inside the car is zero.Hence,it is safer to stay inside a car during a thunderstorm.

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A potentiometer wire of length 1m has a resistance of 10 ohm . It is connected to a 6 v battery in series with a resistance of 5 ohm . Determine the EMF of the primary cell which gives a balance point at 40cm

Posted by Manoj Kumar 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

? ? 5 years, 3 months ago

9volt...apply the formula r=(l1/l2-1)R and put the values of r, l1, and R i.e., 5, 40, and 10 respectively then find the value of l2 which will be 80/3 now put it in the formula E/V=l1/l2 V=6v and l1, l2 are 40 and 80/3 solve it your answer will be 9v.

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What happens if the galvanometer and cells are interchanged at the balance point of the bridge?

Posted by Manoj Kumar 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

? ? 5 years, 3 months ago

The balance point of the meter bridge will shift towards the galvanometer

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A rectangular loop is drawn from left to right across a uniform magnetic field perpendicular to the plane of loop..... Tell the direction of current

Posted by Ashutosh . 5 years, 3 months ago

CBSE > Class 12 > Physics

1 answers

? ? 5 years, 3 months ago

What is the direction of magnetic field?

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For image magnification what lens we need

Posted by Kalakotla Pranith 5 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

? ? 5 years, 3 months ago

Convex lens

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State and prove Bernoulli's theorem for a liquid having stemline flow

Posted by Pritimayee Nanda 5 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

For the streamline flow of non-viscous and incompressible liquid, the sum of potential energy, kinetic energy and pressure energy is constant. ... Since same mass m leaves the pipe at end M in same time t, in which liquid will cover the distance given by v2t. Consider a fluid of negligible viscosity moving with laminar flow, as shown in Figure 1. This is Bernoulli's theorem You can see that if there is a increase in velocity there must be a decrease of pressure and vice versa.

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State and prove Newton's law of cooling

Posted by Pritimayee Nanda 5 years, 4 months ago

CBSE > Class 12 > Physics

1 answers

Meghna Thapar 5 years, 3 months ago

Newton's law of cooling states that the rate at which an object cools is proportional to the difference in temperature between the object and the object's surroundings. Simply put, a glass of hot water will cool down faster in a cold room than in a hot room.

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Prove that the value of of acceleration to due to gravity is more at the surface of the earth than at points above or below (3 marks basic)

Posted by Pritimayee Nanda 5 years, 4 months ago

CBSE > Class 12 > Physics