What is the value of the current in a wire of 10cm long at the right angle to a uniform magnetic field of 0.5 Weber/m2 when the force acting on the wire is 5N ?

Related Mcqs:

1. 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

2. A current carrying conductor is placed in a uniform magnetic field parallel to it. The magnetic force experienced by the conductor is _____________________?

   A. F=1/B
   B. F=1/Bsinθ
   C. F/0
   D. F=1/Bcosθ

3. Magnetic force acting on a unit positive charge moving perpendicular to the magnetic field with a unit velocity is called____________________?

   A. magnetic flux
   B. magnetic field intensity
   C. magnetic induction
   D. self inductance

4. A uniform steel wire of length 4m and area of cross-section 3×10-6m2 is extended by 1mm by the application of a force. If the youngs modulus of steel is 2×1011 Nm-2 the energy stored in the wire is___________________?

   A. 0.025J
   B. 0.50J
   C. 0.75J
   D. 0.100J

5. When a particle of charge q and mass m enters into a uniform magnetic field B moving with a velocity v perpendicular to the direction for the field it describes a circular path of radius___________________?

   A. R=qB/mV
   B. R=mV/qB
   C. R=qmV/B
   D. R=qmB/V

6. The charged particle enters the uniform magnetic field in such a way that its initial velocity is not perpendicular to the field the orbit will be__________________?

   A. a circle
   B. a spiral
   C. an ellipse
   D. helix

7. When an electron moving with a uniform speed in a vacuum enters a magnetic field in a direction perpendicular to the field the subsequent path of the electron is ___________________?

   A. a straight line parallel to the field
   B. a parabola in a plane perpendicular to the field
   C. a circle in a plane perpendicular to the field
   D. a straight line along its initial direction

8. If the plane of the rectangular coil is parallel to the magnetic field (i.e radial magnetic field) the torque on the coil is_____________________?

   A. τ = NIAB cosφ
   B. τ = NIAB sinφ
   C. τ = NIAB tanφ
   D. τ = NIAB

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 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