Energy needed to magnetize and demagnetize is represented by _________________?

Related Mcqs:

1. Geothermal energy is a _______________________ source of energy?

   A. non-renewable
   B. stable
   C. renewable
   D. none of the above

2. ________________ cells converts solar energy into electrical energy?

   A. rotory
   B. photovoltaic
   C. galvanic
   D. non of these

3. In normal state of energy the incident high energy photons will be______________?

   A. Stimulated
   B. Absorbed
   C. Cause X-ray emission
   D. Cause laser production

4. An alternating current is represented by the equation I = I∫sinπt which of the following equation represents an alternating current of frequency and amplitude twice that of the above current ?

   A. I = 2I∫Sin(πt/2)
   B. I = 2I∫Sin(2πt)
   C. I = 2ISinπt
   D. I = I∫sin(2πt)

5. When a force is applied at one end of an elastic wire it produces at strain ∝ in the wire. If y is the youngs modulus of the material of the wire the amount of energy stored per unit volume of the wire is given by_________________?

   A. Y∝
   B. 2Y∝
   C. Y∝/2
   D. Y∝2

6. A certain stress applied to an elastic material produces a certain strain in it. If the elastic limit is not exceeded the energy gained per unit volume of the material is given by_________________?

   A. Stress/strain
   B. (stress/strain)
   C. Stress x strain
   D. (Stress / strain)

7. A wire is stretched by a force F which causes an extension 1. The energy stored in the wire is____________________?

   A. The extension of the wire is proportional to the force applied
   B. The weight of the wire is negligible
   C. The wire is not stretched beyond its elastic limit
   D. The cross sectional area of the wire remains constant

8. The energy band occupied by the valence electrons is called___________________?

   A. Energy state
   B. Valence band
   C. ve energy state
   D. conduction band

9. A wire suspended vertically from one end is stretched by attaching a weight of 20N to the lower end. The weight stretches the wire by 1mm. How much energy is gained by the wire ?

   A. 0.01J
   B. 0.02J
   C. 0.04J
   D. 1.0J

10. A wire obeys Hooks law is of length 11 when it is in equilibrium under a tension F1. Its length becomes 12 when the tension is increased to F2. The energy stored in the wire during this process is____________________?

    A. (F1+F2) (121+122)
    B. (F1+F2) (122-112)
    C. (F1+F2) (12-11)
    D. (F1+F2) (12-11)