XII Physics Solved Numericals | Ch# 18 Magnetic Fields

Board: Sindh Boards
Class : 12, Second Year
Subject: Physics
Unit #18 Magnetic Fields
Numericals:
q. An aluminum window has a width of 60 Frame cm and length of 85 cm as shown in the figure. a. When the window is closed the magnetic flux density is 1.8 x10-4 T is normal to window. b. Calculate the magnetic flux through the window.
2. The poles of a horse shoe magnet measures 8 cm x 3.2cm.the magnetic flux density between the magnet poles is 80mT. Outside of the magnet the magnetic flux density is zero. Calculate the magnetic flux density between the poles of a magnet.
3. A wire 1.80 m long carries a current of 13.0 A and makes an angle of 35.0° with a uniform magnetic field of magnitude B = 1.50 T. Calculate the magnetic force on the wire.
4. A solenoid has length L = 1.23 m and inner diameter d = 3.55 cm, and it carries a current I= 5.57 A. It consists of five close-packed layers, each with 850 turns along length L. What is B at its center?
5. A moving coil galvanometer has resistance of 50 ohms and it gives full scale deflection at 4mA current. A voltmeter is made using this galvanometer and a 5Kohms resistance. Calculate the maximum voltage that can be measured using this voltmeter.
6. Compute the magnitude of the magnetic field of a long, straight wire carrying a current of 1 A at distance of lm from it. Compare it with Earth's magnetic field.
7. Find the current in a long straight wire that would produce a magnetic field twice the strength of the Earth's at a distance of 5.0cm from the wire. (Magnetic field of Earth =5.0x 10-5T).
8. What is flux density atadistanceal 1 m in air from along straight conductor carrying a current of 6.5 A. calculate the force per on a similar parallel conductor at a distance of 0.1m from the first and carrying a current of 3A.