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Name the following diagram and explain the concept behind it. - Science and Technology 1

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प्रश्न

Name the following diagram and explain the concept behind it.

स्पष्ट कीजिए

उत्तर

Fleming's right-hand rule

It represents Fleming's right-hand rule used for finding the direction of induced current with respect to the directions of the magnetic field and motion of the conductor.

The direction of current induced in a conductor can be obtained by holding the thumb, the index finger, and the middle finger of your right hand mutually perpendicular to each other. In this situation, the thumb indicates the direction of the motion of the conductor, the index finger points along the magnetic field, and the middle finger points along the current induced in the conductor.

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अध्याय 4: Effects of electric current - Exercises [पृष्ठ ६१]

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बालभारती Science and Technology 1 [English] 10 Standard SSC Maharashtra State Board
अध्याय 4 Effects of electric current
Exercises | Q 10.1 | पृष्ठ ६१
एससीईआरटी महाराष्ट्र Science and Technology 1 [English] 10 Standard SSC
अध्याय 4 Effects of electric current
Answer the Following | Q 11.1

संबंधित प्रश्न

When a bar magnet is pushed towards (or away) from the coil connected to a galvanometer, the pointer in the galvanometer deflects. Identify the phenomenon causing this deflection and write the factors on which the amount and direction of the deflection depends. State the laws describing this phenomenon.


A circular coil of cross-sectional area 200 cm2 and 20 turns is rotated about the vertical diameter with angular speed of 50 rad s−1 in a uniform magnetic field of magnitude 3.0 × 10−2T. Calculate the maximum value of the current in the coil.


When an electric current is passed through any wire, a magnetic field is produced around it. Then why an electric iron connecting cable does not attract nearby iron objects when electric  current switched on through it?


What condition is necessary for the production of current by electromagnetic induction?


State whether the following statement are true or false: 

 A generator works on the principle of electromagnetic induction. 


 What do you understand by the term "electromagnetic induction"? Explain with the help of a diagram. 


How is the working of an electric bell affected, if alternating current be used instead of direct current?


Name and state the law which determines the direction of induced current.

or

State Fleming’s right-hand rule.


A light metal disc on the top of an electromagnet is thrown up as the current is switched on. Why? Give reason.


A conducting rod is moved with a constant velocity v in a magnetic field. A potential difference appears across the two ends _____________ .


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 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


State Fleming's right hand rule.

Draw a simple labeled diagram of a step-up 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.


Fig. shows a simple form of an A.C. generator.

(a) Name the parts labeled A and B.
(b) What would be the effect of doubling the number of turns on the coil if the speed of rotation remains unchanged?
(c) Which of the output terminals is positive if the coil is rotating in the
direction shown in the diagram (anticlockwise)?
( d ) What is the position of the rotating coil when p.d. across its ends is zero? Explain why p.d. is zero when the coil is at this position .
(e) Sketch a graph showing how the p.d. across the ends of the rotating coil varies with time for an A.C. dynamo.
( f) On th e same sheet of paper and vertically below the first graph using the same time scale, sketch graphs to show the effect of
(i) Doubling the speed of rotation and at the same time keeping
the field and the number of turns constant,
(ii ) Doubling the number of turns on the coil and at the same time
doubling the speed of rotation of the coil, keeping th e speed
constant.


Why do you mean by turns ratio of a transformer? Can it work with D.C.?

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.


What is an electromagnet? List any two uses.


List some of the practical applications of an electromagnet.


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?


Give an illustration of determining direction of induced current by using Lenz’s law.


Obtain an expression for motional emf from Lorentz force.


The laws of electromagnetic induction have been used in the construction of a ______.

Ansari Sir was demonstrating an experiment in his class with the setup as shown in the figure below.

A magnet is attached to a spring. The magnet can go in and out of the stationary coil. He lifted the Magnet and released it to make it oscillate through the coil.
Based on your understanding of the phenomenon, answer the following question.

Consider the situation where the Magnet goes in and out of the coil. State two changes which could be made to increase the deflection in the galvanometer.


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 ______.


A galvanometer is an instrument that can detect the presence of a current in a circuit.


Which of the following phenomena makes use of electromagnetic induction?


AB is a coil of copper wire having a large number of turns. The ends of the coil are connected with a galvanometer as shown. When the north pole of a strong bar magnet is moved towards end B of the coil, a deflection is observed in the galvanometer.

  1. State the reason for using galvanometer in the activity and why does its needle deflects momentarily when magnet is moved towards the coil.
  2. What would be observed in the galvanometer in a situation when the coil and the bar magnet both move with the same speed in the same direction? Justify your answer.
  3. State the conclusion that can be drawn from this activity.
    Will there be any change in the momentary deflection in the galvanometer if number of turns in the coil is increased and a more stronger magnet is moved towards the coil?

OR

What is electromagnetic induction? What is observed in the galvanometer when a strong bar magnet is held stationary near one end of a coil of large number of turns? Justify your answer.


An expression for oscillating electric field in a plane electromagnetic wave is given as Ez = 300 sin(5π × 103x - 3π × 1011t)Vm-1 Then, the value of magnetic field amplitude will be ______. (Given: speed of light in Vacuum c = 3 × 108 ms-1)


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)

 


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