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प्रश्न
Write the two names in the following diagram.
Right hand thumb rule.
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उत्तर
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संबंधित प्रश्न
Electric field intensity in free space at a distance ‘r’ outside the charged conducting sphere of radius ‘R’ in terms of surface charge density ‘ a ’ is............................
(a)`sigma / in_0[R/r]^2`
(b)`in_0/sigma[R/r]^2`
(c)`R/r[sigma/in_0]^2`
(d)`R/sigma[r/in_0]^2`
A solenoid of length 1.5 m and 4 cm in diameter possesses 10 turns per metre. A current of 5 A is flowing through it. The magnetic induction at a point inside the solenoid along the axis is ............................. .
(μ0 = 4π × 10-7 Wb/Am)
- π × 10-5 T
- 2π × 10-5 T
- 3π × 10-5 T
- 4π × 10-5 T
Explain different ways to induce current in a coil.
A rectangular wire loop of sides 8 cm and 2 cm with a small cut is moving out of a region of uniform magnetic field of magnitude 0.3 T directed normal to the loop. What is the emf developed across the cut if the velocity of the loop is 1 cm s−1 in a direction normal to the
- longer side,
- shorter side of the loop?
For how long does the induced voltage last in each case?
State whether the following statement are true or false:
A generator works on the principle of electromagnetic induction.
In which of the following case does the electromagnetic induction occur?
A magnet is moved through a loop of wire .
A light metal disc on the top of an electromagnet is thrown up as the current is switched on. Why? Give reason.
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?
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 ______.
Draw a labelled diagram to show how an electromagnet is made.
List some of the practical applications of an electromagnet.
What is an electromagnet? What do you know about the simplest form of an electromagnet?
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?
Fleming's left hand rule : electric current : : Fleming's right hand rule : _______
Find the odd one out and give its explanation.
Write the two names in the following diagram.
Fleming’s right hand rule.
An electron moves on a straight-line path XY as shown in the figure. The coil abcd is adjacent to the path of the electron. What will be the direction of the current, if any, induced in the coil?
A thin semi-circular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B, as shown in the figure.
The potential difference developed across the ring when its speed v , is
State Lenz’s law.
State Fleming’s right-hand rule.
Give an illustration of determining direction of induced current by using Lenz’s law.
A straight metal wire crosses a magnetic field of flux 4 mWb in a time 0.4 s. Find the magnitude of the emf induced in the wire.
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 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.
An alternating emf of 0.2 V is applied across an L-C-R series circuit having R = 4Q, C = 80µF, and L = 200 mH. At resonance the voltage drop across the inductor is
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 ______
A metal plate can be heated by ______.
Which of the following instruments works by electromagnetic induction?
For making a strong electromagnet the material of the core should be ______.
Sea turtles return to their birth beach many decades after they were born due to ______.
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:
Which of the following phenomena makes use of electromagnetic induction?
A conducting bar of length L is free to slide on two parallel conducting rails as shown in the figure
Two resistors R1 and R2 are connected across the ends of the rails. There is a uniform magnetic field `vec"B"` pointing into the page. An external agent pulls the bar to the left at a constant speed v. The correct statement about the directions of induced currents I1 and I2 flowing through R1 and R2 respectively is:
The primary of a transformer has 400 turns while the secondary has 2000 turns. If the power output from the secondary at 1000 Vis 12 kW, what is the primary voltage?
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 ______.
