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प्रश्न
Two long, straight, parallel conductors carry steady currents, I1 and I2, separated by a distance d. If the currents are flowing in the same direction, show how the magnetic field set up in one produces an attractive force on the other? Obtain the expression for this force. Hence, define one ampere.
उत्तर
Magnetic field induction at some point P on wire 2 due to current I1 passing through wire 1 is given by
`B_1=(mu_0 2I_1)/(4pid)`
As the current-carrying wire 2 lies in magnetic field produced by wire 1, the unit length of wire 2 will experience a force, which is given by
`F=B_1I_2xx1=(mu_0)/(4pi) (2I_1I_2)/d`
According to Fleming's left-hand rule, the force on wire 2 acts in the plane of paper perpendicular to wire 2, directed towards wire 1. Similarly, wire 1 also experiences the same force towards wire 2.
Thus, both the conducting wires attract each other with the same force F.
Thus, one ampere can be defined as the amount of current flowing through two parallel conductors (in the same direction or opposite directions) placed at a distance of one metre in a free space, and both the wires attract or repel each other with a force of 2×10−7 Nm−1 per metre of their lengths.
संबंधित प्रश्न
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Based on the above paragraph, answer the following questions:
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(b) What could be the possible reason for MRI test to be so expensive?
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A particle of charge -16 x 10-18 C moving with velocity 10 m/s along the X-axis enters a region where a magnetic field of induction B is along Y-axis and electric field of magnitude 104 V/m is along the negative Z-axis. If the charged particle continues moving along the X-axis, the magnitude of B is ____________.
Lorentz Force generally refers to ______.
The phenomenon in which a magnetic field is produced in the space near a conductor carrying current is called ______
A charged particle would continue to move with a constant velocity in a region wherein ______.
- E = 0, B ≠ 0.
- E ≠ 0, B ≠ 0.
- E ≠ 0, B = 0.
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