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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
APPEARS IN
संबंधित प्रश्न
State Fleming’s right-hand rule.
A metal rod `1/sqrtpi `m long rotates about one of its ends perpendicular to a plane whose magnetic induction is 4 x 10-3 T. Calculate the number of revolutions made by the rod per second if the e.m.f. induced between the ends of the rod is 16 mV.
Two circular coils A and B are placed closed to each other. If the current in the coil A is changed, will some current be induced in the coil B? Give reason.
A line charge λ per unit length is lodged uniformly onto the rim of a wheel of mass M and radius R. The wheel has light non-conducting spokes and is free to rotate without friction about its axis (Figure). A uniform magnetic field extends over a circular region within the rim. It is given by,
B = − B0 k (r ≤ a; a < R)
= 0 (otherwise)
What is the angular velocity of the wheel after the field is suddenly switched off?
Prove theoretically (electromagnetic induction) `e = (dphi)/(dt)`
An emf of 2V is induced in a coil when the current in it is changed from 0A to 10A in 0·40 sec. Find the coefficient of self-inductance of the coil.
How does an electromagnet differ forma permanent magnet?
State whether the following statement are true or false:
A generator works on the principle of electromagnetic induction.
State whether the following statement are true or false:
A motor works on the principle electric generator?
When a wire is moved up and down in a magnetic field, a current is induced in the wire. What is this phenomenon known as?
When the magnet shown in the diagram below is moving towards the coil, the galvanometer gives a reading to the right.
() What is the name of the effect being produced by the moving magnet?
(2) State what happens to the reading shown on the galvanometer when the magnet is moving away from the coil.
(3) The original experiment is repeated. This time the magnet is moved towards the coil at a great speed. State two changes you would notice in the reading on the galvanometer.
Describe one experiment to demonstrate the phenomenon of electromagnetic induction.
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.
The coil of a moving-coil galvanometer keeps on oscillating for a long time if it is deflected and released. If the ends of the coil are connected together, the oscillation stops at once. Explain.
Calculate the dimensions of (a) \[\int \overrightarrow{E} . d \overrightarrow{l,}\] (b) vBl and (c) \[\frac{d \Phi_B}{dt}.\] The symbols have their usual meaning.
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?
Figure shows a long U-shaped wire of width l placed in a perpendicular magnetic field B. A wire of length l is slid on the U-shaped wire with a constant velocity v towards right. The resistance of all the wires is r per unit length. At t = 0, the sliding wire is close to the left edge of the U-shaped wire. (a) Calculate the force needed to keep the sliding wire moving with a constant velocity v. (b) If the force needed just after t = 0 is F0, find the time at which the force needed will be F0/2.0
Fill in the blanks by writing (i) Only soft iron, (ii) Only steel, (iii) Both soft-iron and steel for the material of core and/or magnet.
D.C. motor ______.
A transformer has 400 turns in the primary winding and 10 turns in the secondary winding. The primary e.m.f. is 250 V and the primary current is 2.0 A. calculate:
(a) The secondary voltage,
(b) The secondary current, assuming 100% efficiency.
Draw a labelled diagram to show how an electromagnet is made.
List some of the practical applications of an electromagnet.
The energy stored in a 50 mH inductor carrying a current of 4 A is ______
State the condition at which we say the two coils kept close to each other are perfectly coupled with each other.
Using Ampere's law, obtain an expression for the magnetic induction near a current-carrying straight infinitely long wire.
Find the odd one out and give its explanation.
Write Fleming’s right hand thumb rule with the help of diagram.
State Lenz’s law.
What for an inductor is used? Give some examples.
Give an illustration of determining direction of induced current by using Lenz’s law.
Using Lenz’s law, predict the direction of induced current in conducting rings 1 and 2 when the current in the wire is steadily decreasing.
A cylindrical bar magnet is kept along the axis of a circular coil. If the magnet is rotated about its axis, then ____________.
A generator has an e.m.f. of 440 Volt and internal resistance of 4000 hm. Its terminals are connected to a load of 4000 ohm. The voltage across the load is ______.
If the sun radiates energy at the rate of 3.6 × 1033 ergs/sec the rate at which the sun is loosing mass is given by ______.
Sea turtles return to their birth beach many decades after they were born due to ______.
A galvanometer is an instrument that can detect the presence of a current in a circuit.
In the current carrying conductor (AOCDEFG) as shown, the magnetic induction at point O is ______.
(R1 and R2 are radii of CD and EF respectively. l = current in the loop, μ0 = permeability of free space)
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 ______.
Which type of force is experienced by a moving charge in a magnetic field?
