Amperes law provides another method to determine the magnetic field due to a given current distribution.
Line integral of the given magnetic field around any closed curve is equal to times the net
current i threading through the area enclosed by the curve
i.e.
Also using (where H = magnetising field)
|
|
Magnetic field due to an infinite sheet carrying current: The figure shows an infinite sheet of current with linear current density j (A/m). Due to symmetry the field line pattern above and below the sheet is uniform. Consider a square loop of side l as shown in the figure.
According to Ampere's law, .
Since B ^ dl along the path b → c and d → a, therefore, ;
Also, B || dl along the path a → b and c → d, thus
The current enclosed by the loop is i = jl
Therefore, according to Ampere's law or B = μoj/2
Solenoid: A cylindrical coil of many tightly wound turns of insulated wire with generally diameter of the coil smaller than its length are called a solenoid.
One end of the solenoid behaves like the North Pole and opposite end behaves like the South Pole. As the size of the solenoid increases, the interior space converts into more uniform and the external field becomes weaker.
A magnetic field is produced around and within the solenoid. The magnetic space within the solenoid is parallel and uniform to the axis of solenoid.
(i) Finite length solenoid : If N = total number of turns,
l = length of the solenoid
n = number of turns per unit length = N/l
|
|
Magnetic field under the solenoid at position P is given by
(ii) Infinite length solenoid: If the solenoid is of infinite length and the point is well inside the solenoid.
So Bin = μoni
(iii) If the solenoid is of infinite length and the point is near one end i.e. a=0 and b = π/2
So Bend = 1/2(μoni)
Email based Physics assignment help - homework help at Expertsmind
Are you searching physics expert for help with Ampere's law questions? Ampere's law topic is not easier to learn without external help? We at www.expertsmind.com offer finest service of Physics assignment help and physics homework help. Live tutors are available for 24x7 hours helping students in their Ampere's law related problems. We provide step by step Ampere's law question's answers with 100% plagiarism free content. We prepare quality content and notes for Ampere's law topic under physics theory and study material. These are avail for subscribed users and they can get advantages anytime.
Why Expertsmind for assignment help
- Higher degree holder and experienced experts network
- Punctuality and responsibility of work
- Quality solution with 100% plagiarism free answers
- Time on Delivery
- Privacy of information and details
- Excellence in solving physics queries in excels and word format.
- Best tutoring assistance 24x7 hours