Advertisements
Advertisements
प्रश्न
What is Lorentz force?
उत्तर
When a charged particle moves through a region in which both electric and magnetic fields are present, then the net force experienced by that charged particle is the sum of electrostatic force and magnetic force and is called the Lorentz force.
APPEARS IN
संबंधित प्रश्न
A rod of length l is moved horizontally with a uniform velocity 'v' in a direction perpendicular to its length through a region in which a uniform magnetic field is acting vertically downward. Derive the expression for the emf induced across the ends of the rod.
A long straight wire carries a current of 35 A. What is the magnitude of the field B at a point 20 cm from the wire?
A horizontal overhead power line carries a current of 90 A in east to west direction. What is the magnitude and direction of the magnetic field due to the current 1.5 m below the line?
Explain the term hysteresis
A steady current (I1) flows through a long straight wire. Another wire carrying steady current (I2) in the same direction is kept close and parallel to the first wire. Show with the help of a diagram how the magnetic field due to the current I1 exerts a magnetic force on the second wire. Write the expression for this force.
The net charge in a current-carrying wire is zero. Then, why does a magnetic field exert a force on it?
Two wires carrying equal currents i each, are placed perpendicular to each other, just avoiding a contact. If one wire is held fixed and the other is free to move under magnetic forces, what kind of motion will result?
A conductor has three segments; two straights of length L and a semicircular with radius R. It carries a current I What is the magnetic field B at point P?
A proton enters into a magnetic field of induction 1.732 T, with a velocity of 107 m/s at an angle 60° to the field. The force acting on the proton is e = 1.6 × 10-19 C, sin 60° = cos 30° = `sqrt3/2`
An electron emitted by a heated cathode and accelerated through a potential difference of 2.0 kV, enters a region with uniform magnetic field of 0.15 T. Determine the trajectory of the electron if the field (a) is transverse to its initial velocity, (b) makes an angle of 30° with the initial velocity.
A magnetic field set up using Helmholtz coils is uniform in a small region and has a magnitude of 0.75 T. In the same region, a uniform electrostatic field is maintained in a direction normal to the common axis of the coils. A narrow beam of (single species) charged particles all accelerated through 15 kV enters this region in a direction perpendicular to both the axis of the coils and the electrostatic field. If the beam remains undeflected when the electrostatic field is 9.0 × 10–5 V m–1, make a simple guess as to what the beam contains. Why is the answer not unique?
A solenoid 60 cm long and of radius 4.0 cm has 3 layers of windings of 300 turns each. A 2.0 cm long wire of mass 2.5 g lies inside the solenoid (near its centre) normal to its axis; both the wire and the axis of the solenoid are in the horizontal plane. The wire is connected through two leads parallel to the axis of the solenoid to an external battery which supplies a current of 6.0 A in the wire. What value of current (with appropriate sense of circulation) in the windings of the solenoid can support the weight of the wire? (g = 9.8 m s–2)
Lorentz Force generally refers to ______.
The correct plot of the magnitude of magnetic field `vec"B"` vs distance r from centre of the wire is, if the radius of wire is R.
An infinitely long straight conductor carries a current of 5 A as shown. An electron is moving with a speed of 105 m/s parallel to the conductor. The perpendicular distance between the electron and the conductor is 20 cm at an instant. Calculate the magnitude of the force experienced by the electron at that instant.
An infinitely long straight conductor carries a current of 5 A as shown. An electron is moving with a speed of 105 m/s parallel to the conductor. The perpendicular distance between the electron and the conductor is 20 cm at an instant. Calculate the magnitude of the force experienced by the electron at that instant.
Consider a wire carrying a steady current, I placed in a uniform magnetic field B perpendicular to its length. Consider the charges inside the wire. It is known that magnetic forces do no work. This implies that ______.
- motion of charges inside the conductor is unaffected by B since they do not absorb energy.
- some charges inside the wire move to the surface as a result of B.
- if the wire moves under the influence of B, no work is done by the force.
- if the wire moves under the influence of B, no work is done by the magnetic force on the ions, assumed fixed within the wire.
The magnetic force depends on v which depends on the inertial frame of reference. Does then the magnetic force differ from inertial frame to frame? Is it reasonable that the net acceleration has a different value in different frames of reference?
A long straight wire carrying current of 25 A rests on a table as shown in figure. Another wire PQ of length 1 m, mass 2.5 g carries the same current but in the opposite direction. The wire PQ is free to slide up and down. To what height will PQ rise?
The unit Wbm-2 is equal to ______.
Two long current-carrying conductors are placed parallel to each other at a distance of 8 cm between them. The magnitude of the magnetic field produced at the mid-point between the two conductors due to the current flowing in them is 300µT. The equal current flowing in the two conductors is ______.
A unit vector is represented as `(0.8hat"i" + "b"hat"j" + 0.4hat"k")`. Hence the value of 'b' must be ______.
State the expression for the Lorentz force on a charge due to an electric field as well as a magnetic field. Hence discuss the magnetic force on a charged particle which is (i) moving parallel to the magnetic field and (ii) stationary.
Two long parallel current-carrying conductors are 0.4 m apart in air and carry currents 5 A and 10 A. Calculate the force per metre on each conductor, if the currents are (a) in the same direction and (b) in the opposite direction.
State dimensions of magnetic field.
Lorentz force in vector form is ______.
