BOOKS FOR REFERENCE

1. H. C. Verma, Concepts of Physics – Volume

2. Halliday, Resnick and Walker, Fundamenta

3. Serway and Jewett, Physics for scientist and publishers, Eighth edition.

4. David J. Griffiths, Introduction to electrodyn

5. Rita John, Solid State Physics (Magnetism c Ltd.

6. Paul Tipler and Gene Mosca, Physics for Sixth edition, W.H. Freeman and Company

(b) total force on the coil (c) average force on each electron in the

coil due to the magnetic field. (The free electron density for the material of the wire is 1028 m–3).

Answer (a) zero (b) zero (c) 0.6 x 10**–23** N 4. A bar magnet is placed in a uniform

magnetic field whose strength is 0.8 T. If the bar magnet is oriented at an angle 30o with the external field experiences a torque of 0.2 Nm. Calculate:

(i) the magnetic moment of the magnet (ii) the work done by the magnetic field

in moving it from most stable configuration to the most unstable configuration and also compute the work done by the applied magnetic field in this case.

Answer (i) 0.5 A m2 (ii) W = 0.8 J and _W_mag = -0.8 J

5. A non - conducting sphere has a mass of 100 g and radius 20 cm. A flat compact coil of wire with turns 5 is

2, Bharati Bhawan Publisher.

ls of Physics, Wiley Publishers, 10th edition.

engineers with modern physics, Brook/Coole

amics, Pearson publishers.

hapter), McGraw Hill Education (India) Pvt.

scientist and engineers with modern physics, .

wrapped tightly around it with each turns concentric with the sphere. This sphere is placed on an inclined plane such that plane of coil is parallel to the inclined plane. A uniform magnetic field of 0.5 T exists in the region in vertically upward direction. Compute the current I required to rest the sphere in equilibrium. Answer 2

π A

6. Calculate the magnetic field at the centre of a square loop which carries a current of 1.5 A, length of each side being 50 cm. Answer 3.4 x 10–6 T

ICT CORNER Magnetism

In this activity you will be able to visualize and understand the working of cyclotron.

STEPS:

• Open the browser and type ‘physics.bu.edu/~duffy/HTML5/cyclotron.html’ in the address bar.
• Click ‘play’ to release the positively charged particle between the D-shaped sections.
• Observe trajectory of positively charged particle under the magnetic field between D-shaped sections.
• Note the kinetic energy of the particle after some time (say t = 20 s)

URL: http://physics.bu.edu/~duffy/HTML5/cyclotron.html

* Pictures are indicative only. * If browser requires, allow Flash Player or Java Sc