मराठी
महाराष्ट्र राज्य शिक्षण मंडळएचएससी विज्ञान (सामान्य) इयत्ता १२ वी

State Ampere’s circuital law. - Physics

Advertisements
Advertisements

प्रश्न

State Ampere’s circuital law.

State Ampere’s circuital law, expressing it in the integral form.

लघु उत्तर
Advertisements

उत्तर १

Ampere’s circuital law states that the line integral of magnetic field induction `vecB`  around a closed path in vacuum is equal to μ0 times the total current I passing through the surface, i.e. `ointvecB.vec(dl)=mu_0I`

shaalaa.com

उत्तर २

Ampere’s Circuital Law states that the circulation of the resultant magnetic field along a closed, plane curve is equal to μo times the total current crossing the area bounded by the closed curve, provided the electric field inside the loop remains constant.

In the above illustration, the Ampere’s Circuital Law can be written as follows:

`ointvecB.vec(dl) = mu_0 i`

where, i = |i1 i2|

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
2014-2015 (March) Delhi Set 2

व्हिडिओ ट्यूटोरियलVIEW ALL [2]

संबंधित प्रश्‍न

Write Maxwell's generalization of Ampere's circuital law. Show that in the process of charging a capacitor, the current produced within the plates of the capacitor is `I=varepsilon_0 (dphi_E)/dt,`where ΦE is the electric flux produced during charging of the capacitor plates.


State Ampere’s circuital law.


Electron drift speed is estimated to be of the order of mm s−1. Yet large current of the order of few amperes can be set up in the wire. Explain briefly.


A 3.0 cm wire carrying a current of 10 A is placed inside a solenoid perpendicular to its axis. The magnetic field inside the solenoid is given to be 0.27 T. What is the magnetic force on the wire?


Obtain an expression for magnetic induction along the axis of the toroid.


Explain Ampere’s circuital law.


Using Ampere’s circuital law, obtain the expression for the magnetic field due to a long solenoid at a point inside the solenoid on its axis ?


A long straight wire of a circular cross-section of radius ‘a’ carries a steady current ‘I’. The current is uniformly distributed across the cross-section. Apply Ampere’s circuital law to calculate the magnetic field at a point ‘r’ in the region for (i) r < a and (ii) r > a.


A long, straight wire carries a current. Is Ampere's law valid for a loop that does not enclose the wire, or that encloses the wire but is not circular?


In order to have a current in a long wire, it should be connected to a battery or some such device. Can we obtain the magnetic due to a straight, long wire by using Ampere's law without mentioning this other part of the circuit? 


A hollow tube is carrying an electric current along its length distributed uniformly over its surface. The magnetic field
(a) increases linearly from the axis to the surface
(b) is constant inside the tube
(c) is zero at the axis
(d) is zero just outside the tube.


Consider the situation described in the previous problem. Suppose the current i enters the loop at the points A and leaves it at the point B. Find the magnetic field at the centre of the loop. 


A thin but long, hollow, cylindrical tube of radius r carries i along its length. Find the magnitude  of the magnetic field at a distance r/2 from the surface (a) inside the tube (b) outside the tube.


A long, cylindrical tube of inner and outer  radii a and b carries a current i distributed uniformly over its cross section. Find the magnitude of the magnitude filed at a point (a) just inside the tube (b) just outside the tube.


Sometimes we show an idealised magnetic field which is uniform in a given region and falls to zero abruptly. One such field is represented in figure. Using Ampere's law over the path PQRS, show that such a field is not possible. 


Consider the situation of the previous problem. A particle having charge q and mass mis projected from the point Q in a direction going into the plane of the diagram. It is found to describe a circle of radius r between the two plates. Find the speed of the charged particle.


What is magnetic permeability?


Calculate the magnetic field inside and outside of the long solenoid using Ampere’s circuital law


The wires which connect the battery of an automobile to its starting motor carry a current of 300 A (for a short time). What is the force per unit length between the wires if they are 70 cm long and 1.5 cm apart? Is the force attractive or repulsive?


A straight wire of diameter 0.5 mm carrying a current of 1 A is replaced by another wire of 1 mm diameter carrying the same current. The strength of the magnetic field far away is ______.


Ampere’s circuital law states that ______.

Ampere’s circuital law is equivalent to ______.

Which of the following is the correct definition of ampere?

Ampere’s circuital law is given by _______.


In a capillary tube, the water rises by 1.2 mm. The height of water that will rise in another capillary tube having half the radius of the first is:


A solenoid of length 0.6 m has a radius of 2 cm and is made up of 600 turns If it carries a current of 4 A, then the magnitude of the magnetic field inside the solenoid is:


A long solenoid having 200 turns per cm carries a current of 1.5 amp. At the centre of it is placed a coil of 100 turns of cross-sectional area 3.14 × 10−4 m2 having its axis parallel to the field produced by the solenoid. When the direction of current in the solenoid is reversed within 0.05 sec, the induced e.m.f. in the coil is:


Ampere's circuital law is used to find out ______


Two identical current carrying coaxial loops, carry current I in an opposite sense. A simple amperian loop passes through both of them once. Calling the loop as C ______.

  1. `oint B.dl = +- 2μ_0I`
  2. the value of `oint B.dl` is independent of sense of C.
  3. there may be a point on C where B and dl are perpendicular.
  4. B vanishes everywhere on C.

Two concentric and coplanar circular loops P and Q have their radii in the ratio 2:3. Loop Q carries a current 9 A in the anticlockwise direction. For the magnetic field to be zero at the common centre, loop P must carry ______.


The given figure shows a long straight wire of a circular cross-section (radius a) carrying steady current I. The current I is uniformly distributed across this cross-section. Calculate the magnetic field in the region r < a and r > a.

 


Using Ampere’s circuital law, obtain an expression for magnetic flux density ‘B’ at a point near an infinitely long and straight conductor, carrying a current I.


When current flowing through a solenoid decreases from 5A to 0 in 20 milliseconds, an emf of 500V is induced in it.

  1. What is this phenomenon called?
  2. Calculate coefficient of self-inductance of the solenoid.

Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×