Advertisements
Advertisements
प्रश्न
The motion of copper plate is damped when it is allowed to oscillate between the two poles of a magnet. What is the cause of this damping?
Advertisements
उत्तर
As the copper plates oscillate in the magnetic field between the two poles of the magnet, there is a continuous change of magnetic field flux linked with the plate. Due to this, eddy currents are set up in the copper plate which try to oppose the motion of the plate according to the Lenz’s law and finally bring it to rest.
संबंधित प्रश्न
Two identical coils P and Q each of radius R are lying in perpendicular planes such that they have a common centre. Find the magnitude and direction of the magnetic field at the common centre of the two coils, if they carry currents equal to I and \[\sqrt{3}\] I respectively.
Show with the help of a diagram how the force between the two conductors would change when the currents in them flow in the opposite directions?
Consider the situation shown in figure. The wire PQ has mass m, resistance r and can slide on the smooth, horizontal parallel rails separated by a distance l. The resistance of the rails is negligible. A uniform magnetic field B exists in the rectangular region and a resistance R connects the rails outside the field region. At t = 0, the wire PQ is pushed towards right with a speed v0. Find (a) the current in the loop at an instant when the speed of the wire PQ is v, (b) the acceleration of the wire at this instant, (c) the velocity vas a functions of x and (d) the maximum distance the wire will move.
The current generator Ig' shown in figure, sends a constant current i through the circuit. The wire ab has a length l and mass m and can slide on the smooth, horizontal rails connected to Ig. The entire system lies in a vertical magnetic field B. Find the velocity of the wire as a function of time.
A charged particle moving in a magnetic field experiences a resultant force ______
A circular coil of radius 10 cm is placed in a uniform magnetic field of 3.0 × 10-5 T with its plane perpendicular to the field initially. It is rotated at constant angular speed about an axis along the diameter of coil and perpendicular to magnetic field so that it undergoes half of rotation in 0.2 s. The maximum value of EMF induced (in µV) in the coil will be close to the integer ______.
A conductor ABOCD moves along its bisector with a velocity 1 m/s through a perpendicular magnetic field of 1 wb/m2, as shown in figure. If all the four sides are 1 m length each, then the induced emf between A and Din approx is ______V.
A charge Q is moving `vec"dl"` distance in the magnetic field `vec"B"`. Find the value of work done by `vec"B"`.
An electron (mass 9 × 10−31 kg and charge 1.6 × 10−19 C) moving with speed c/100 (c = speed of light)is injected into a magnetic field `vecB` of magnitude 9 × 10−4 T perpendicular to its direction of motion. We wish to apply an uniform electric field `vecE` together with the magnetic field so that the electron does not deflect from its path. Then (speed of light c = 3 × 108 m s−1).
An electron (mass \[9 \times 10^{-31}\] kg, charge \[1.6 \times 10^{-19}\] C) moves at \[3 \times 10^7\] m/s in a magnetic field of \[6 \times 10^{-4}\] T perpendicular to its velocity. The radius of its circular path is:
