Section 16.2 Magnetic Effect of Electric Current

8/14/2019 Section 16.2 Magnetic Effect of Electric Current

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Manhattan Press (H.K.) Ltd. 1

Section 16.2Section 16.2

Magnetic effect ofMagnetic effect of

electric currentelectric current

Section 16.2Section 16.2

Magnetic effect ofMagnetic effect of

electric currentelectric current

Current-carrying circular coilCurrent-carrying circular coil

Current-carrying straight wireCurrent-carrying straight wire

Current-carrying solenoidCurrent-carrying solenoid


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Magnetic effect of electric current

Magnetic field produced by magnet

16.2 Magnetic effect of electric current (SB p. 111)

Go to

Discussion 2Discussion 2

moving electric charges

electric current

magnetic effect of an electric current


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Magnetic field

concentric circles with wire

at centre

Current-carrying straight wire



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currentoutoftheplane




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currentintotheplane




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magnetic field predicted by

right hand

field lines

current

Right-hand grip rule for current-carrying

straight wire


right-hand grip rule


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right hand

field lines

current


straight wire



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right hand

field lines

current


straight wire



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Current-carrying circular coil

Expt. 16B

Magnetic effect

of current

B. Magnetic

field due tocurrent-carrying

circular coil


circular coil

d.c. power supply

plastic board
http://movie/Expt%2016B/16B.avi


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Current-carrying circular coil



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Magnetic field

points upwards

Magnetic field points

into paper


circular coil



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Current-carrying solenoid

Expt. 16B

Magnetic effect

of current

C. Magnetic

field due tocurrent-carrying

solenoid


solenoid

d.c. power supplyplastic board
http://movie/Expt%2016B/16B.avi


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uniform

Current-carrying solenoid



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solenoid


Thinking 4Thinking 4


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Example 1:Example 1:The following figure shows a solenoid placed on a table. If

two compasses are placed at Xand Yon the table, drawthe needles of the compasses when

(a) switch K is open, and

(b) switch K is closed.

(The needles of the compasses point to the north.)

Solution


(a)

(b)


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To section 16.3
http://e-ch16_03.ppt/http://e-ch16_03.ppt/


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Discussion 2:Discussion 2:

1. With the help of a magnet, suggest a methodto make an iron bar attract some paper clips.

Discuss with your classmates. Answer


(a) Touch the iron bar with the magnet, and then the

iron bar can attract the paper clips.

(b) Magnetize the iron bar by sliding the north pole of

the magnet along the bar many times in the same

direction. Then the iron bar can attract the paper

clips.

S N


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Discussion 2: (Cont)Discussion 2: (Cont)

2. A compass is wound with several turns of awire. The wire is connected to a dry cell to

form a closed circuit. What happens to the

needle of the compass?

Discuss with your classmates.

The needle is deflected.

Return to

TextText


Ans

wer


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The diagram shows two long and parallelcurrent-carrying wires. Point Q is at equal

distance from the two wires. Find the direction of

the resulting magnetic fields at pointP

,Q

andR

.

Thinking 4Thinking 4

Ans

wer

Return to

TextText

At Q, the magnetic field by I1

is pointing out of the paper,

but the magnetic field by I2 ispointing in of the paper.

Therefore, there is no magnetic

field at Q.


Section 16.2 Magnetic Effect of Electric Current

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Transcript of Section 16.2 Magnetic Effect of Electric Current