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प्रश्न
Fleming's left hand rule : electric current : : Fleming's right hand rule : _______
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उत्तर
Fleming's left hand rule : electric current : : Fleming's right hand rule : direction of induced current
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संबंधित प्रश्न
The magnetic flux through a loop varies according to the relation Φ = 8t2 + 6t + C, where ‘C’ is constant, 'Φ' is in milliweber and 't' is in second. What is the magnitude of induced e.m.f. in the loop at t = 2 seconds.
The phenomenon of electromagnetic induction is
A horizontal straight wire 10 m long extending from east to west is falling with a speed of 5.0 m s−1, at right angles to the horizontal component of the earth’s magnetic field, 0.30 × 10−4 Wb m−2.
- What is the instantaneous value of the emf induced in the wire?
- What is the direction of the emf?
- Which end of the wire is at the higher electrical potential?
Explain why, an electromagnet is called a temporary magnet.
State the factors on which the strength of an electromagnet depends. How does it depend on these factors?
What condition is necessary for the production of current by electromagnetic induction?
Describe different ways to induce current in a coil of wire.
An induced current is produced when a magnet is moved into a coil. The magnitude of induced current does not depend on:
(a) the speed with which the magnet is moved
(b) the number of turns of the coil
(c) the resistivity of the wire of the coil
(d) the strength of the magnet
In which of the following case does the electromagnetic induction occur?
The current is stopped in a wire held near a loop of wire .
Name and state the law which determines the direction of induced current.
or
State Fleming’s right-hand rule.
Welders wear special goggles or face masks with glass windows to protect their eyes from electromagnetic radiations. Name the radiations and write the range of their frequency.
A light metal disc on the top of an electromagnet is thrown up as the current is switched on. Why? Give reason.
Show diagrammatically how an alternating emf is generated by a loop of wire rotating in a magnetic field. Write the expression for the instantaneous value of the emf induced in the rotating loop.
Electromagnetic induction means ______.
A conducting square loop having edges of length 2.0 cm is rotated through 180° about a diagonal in 0.20 s. A magnetic field B exists in the region which is perpendicular to the loop in its initial position. If the average induced emf during the rotation is 20 mV, find the magnitude of the magnetic field.
Figure shows a wire sliding on two parallel, conducting rails placed at a separation l. A magnetic field B exists in a direction perpendicular to the plane of the rails. What force is necessary to keep the wire moving at a constant velocity v?
Draw a simple labeled diagram of a step-down transformer.
The diagram 10 shows two coils X and Y. The coil X is connected to a battery S and a key K. The coil Y is connected to a galvanometer G.
When the key K is closed. State the polarity
(i)At the end of the coil X,
(ii)At the end C of the coil Y,
(iii)At the end C of the coil Y if the coil Y is (a) Moved towards the coil X, (b) Moved away from the coil X.
Complete the following diagram of a transformer and name the parts labeled A and B. Name the part you have drawn to complete the diagram . What is the material of this part? In this transformer a step-up or step-down? Why?
Answer the following:
State the principles of the electric motor and electric generator.
Draw a labelled diagram to show how an electromagnet is made.
Using Ampere's law, obtain an expression for the magnetic induction near a current-carrying straight infinitely long wire.
Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.
Which of the following scientist invented the rule of electromagnetic induction?
What for an inductor is used? Give some examples.
Establish the fact that the relative motion between the coil and the magnet induces an emf in the coil of a closed circuit.
An induced current of 2.5 mA flows through a single conductor of resistance 100 Ω. Find out the rate at which the magnetic flux is cut by the conductor.
A coil of 200 turns carries a current of 4 A. If the magnetic flux through the coil is 6 x 10-5 Wb, find the magnetic energy stored in the medium surrounding the coil.
A 50 cm long solenoid has 400 turns per cm. The diameter of the solenoid is 0.04 m. Find the magnetic flux linked with each turn when it carries a current of 1 A.
Shown in the figure below is a metre bridge set up with null deflection in the galvanometer. The value of the unknown resistance R is ______
The condition for the praenomen of electromagnetic induction is that there must be a relative motion between ____________.
We can induce the current in a coil by ____________.
A coil of one turn is made of a wire of certain length and then from the same length, a coil of two turns is made. If the same current is passed in both the cases, then the ratio of the magnetic inductions at their centres will be:
A 0.4 m wire, stretched horizontally, carries an electric current of 15 A, in a magnetic field whose magnetic field intensity is 0.1 N/Am. What is the magnitude of the wire?
The charge will flow through a galvanometer of resistance 200Ω connected to a 400Ω circular coil of 1000 turns wound on a wooden stick 20 mm in diameter, if a magnetic field B = 0.012 T parallel to the axis of the stick decreased suddenly to zero, is near ______.
When an electric current is passed through a wire or a coil, a magnetic field is produced. Is the reverse phenomenon possible i.e, can a magnetic field produce an electric current? Explain with the help of an appropriate example.
