Advertisements
Advertisements
प्रश्न
A circular coil of 20 turns and radius 10 cm is placed in a uniform magnetic field of 0.10 T normal to the plane of the coil. If the current in the coil is 5.0 A, what is the
(a) total torque on the coil,
(b) total force on the coil,
(c) average force on each electron in the coil due to the magnetic field?
(The coil is made of copper wire of cross-sectional area 10–5 m2, and the free electron density in copper is given to be about 1029 m–3.)
उत्तर
Number of turns on the circular coil, n = 20
Radius of the coil, r = 10 cm = 0.1 m
Magnetic field strength, B = 0.10 T
Current in the coil, I = 5.0 A
(a) The total torque on the coil is zero because the field is uniform.
(b) The total force on the coil is zero because the field is uniform.
(c) Cross-sectional area of copper coil, A = 10−5 m2
Number of free electrons per cubic meter in copper, N = 1029/m3
Charge on the electron, e = 1.6 × 10−19 C
Magnetic force, F = Bevd
Where,
vd = Drift velocity of electrons
= `"I"/("NeA")`
∴ F = `"BeI"/"NeA"`
= `(0.10 xx 5.0)/(10^29 xx 10^-5)`
= 5 × 10−25 N
Hence, the average force on each electron is 5 × 10−25 N.
APPEARS IN
संबंधित प्रश्न
A circular loop of radius a, carrying a current i, is placed in a two-dimensional magnetic field. The centre of the loop coincides with the centre of the field (figure). The strength of the magnetic field at the periphery of the loop is B. Find the magnetic force on the wire.
A circular loop of one turn carries a current of 5.00 A. If the magnetic field B at the centre is 0.200 mT, find the radius of the loop.
A Rectangular coil of 10 turns, each of area 0.05 m2, is suspended freely in a uniform magnetic field of induction 0.01 T. A current of 30 µA is passed through it.
(i) What is the magnetic moment of the coil?
(ii) What is the maximum torque experienced by the coil?
A rectangular coil of length 0.12 m and width 0.1 m having 100 turns of wire is suspended vertically in a uniform magnetic field of strength 0.4 Wb/m2. The coil carries a current of 2.5 A. If the plane of the coil is inclined at an angle of 30° with the direction of the field, the torque required to keep the coil in stable equilibrium will be ____________.
If number of turns in moving coil galvanometer becomes half, then the deflection for the same current will become ____________.
In suspended type of moving coil galvanometer ____________.
The magnetic field developed due to current carrying coil at its centre is 'B'. If the new coil of two turns is prepared from the above coil and same current is passed, then the magnetic field at the centre of the new coil will be ____________.
An ammeter is obtained by shunting 'n' `Omega` galvanometer with 'n' `Omega` resistance. The additional shunt required to be connected across it to double the range is ____________.
A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field `Bhati`. The torque on the coil due to the magnetic field is ______.
Equal current i flows in two segments of a circular loop in the direction shown in figure. Radius of the loop is r. The magnitude of magnetic field induction at the centre of the loop is ______.
