English
Maharashtra State BoardSSC (English Medium) 10th Standard

Electromagnetic induction means ______.

Advertisements
Advertisements

Question

Electromagnetic induction means ______.

Options

  • Charging of an electric conductor.

  • Production of magnetic field due to a current flowing through a coil.

  • Generation of a current in a coil due to relative motion between the coil and the magnet.

  • Motion of the coil around the axle in an electric motor.

MCQ
Fill in the Blanks
Advertisements

Solution

Electromagnetic induction means generation of a current in a coil due to relative motion between the coil and the magnet.

shaalaa.com
  Is there an error in this question or solution?
Chapter 4: Effects of electric current - Exercises [Page 60]

APPEARS IN

Balbharati Science and Technology Part 1 [English] Standard 10 Maharashtra State Board
Chapter 4 Effects of electric current
Exercises | Q 3 | Page 60

RELATED QUESTIONS

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 ............................. .

0 = 4π × 10-7 Wb/Am)

  1. π  × 10-5 T
  2. 2π × 10-5 T
  3. 3π × 10-5 T
  4. 4π × 10-5 T

State three differences between direct current and alternating current.


Explain different ways to induce current in a coil.


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 is an electromagnet? Describe the construction and working of an electromagnet with the help of a labelled diagram.


The direction of current in the coil at one end of an electromagnet is clockwise. This end of the electromagnet will be:

(a) north pole
(b) east pole
(c) south pole
(d) west pole


The most suitable material for making the core of an electromagnet is:

(a) soft iron
(b) brass
(c) aluminium
(d) steel


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 conducting square loop of side l and resistance R moves in its plane with a uniform velocity v perpendicular to one of its sides. A uniform and constant magnetic field Bexists along the perpendicular to the plane of the loop as shown in figure. The current induced in the loop is _____________ .


L, C and R represent the physical quantities inductance, capacitance and resistance respectively. Which of the following combinations have dimensions of frequency?

(a) `1/(RC)`

(b) `R/L`

(c) `1/sqrt(LC)`

(d) C/L


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?


Can you find the magnitude of current using Fleming's right hand rule?

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.


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

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 coil has a self-inductance of 0·05 Henry. Find the magnitude of the emf induced in it when the current flowing through it is changing at the rate of 100 As-1.


State Fleming’s Right Hand Rule.


State the purpose of soft iron core used in making an electromagnet.


List two ways of increasing the strength of an electromagnet if the material of the electromagnet is fixed.


You have been provided with a solenoid AB.

(i) What is the polarity at end A?
(ii) Give one advantage of an electromagnet over a permanent magnet.


Choose the correct option:

A conductor rod of length (l) is moving with velocity (v) in a direction normal to a uniform magnetic field (B). What will be the magnitude of induced emf produced between the ends of the moving conductor?


Observe the given figure of Fleming’s Right Hand Rule and write the labels of A and B correctly.


The right-hand thumb rule is also called _______ rule.


Which of the following scientist invented the rule of electromagnetic induction?


State Fleming’s right-hand rule.


What for an inductor is used? Give some examples.


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.


For magnetic breaking in trains, strong electromagnets are situated above the rails in some electrically powered trains. When the electromagnets are activated, the ...A... induced in the rails oppose the motion of the train. As there are no ... B... linkages, the ...C... effects is smooth. Here, A, B and C refer to ______.

The instrument that use to defect electric current in the circuit is known as ____________.


What should be the core of an electromagnet?


Name some equipment that uses electromagnetism for functioning.


The working of a dynamo is based on the principle of


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.


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?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×