STPM Physics Chapter 16 Magnetic Fields

STPM PHYSICS CHAPTER 16 MAGNETIC FIELDS

SMK SACRED HEART, SIBU 1.

Magnetic field = field of force produced by current-carrying conductors or by permanent magnets. 2. Magentic force of moving charge F = Bqv  Moving of electron produced current. With presence of current, thus use Left-Hand rule  B, q and v must be perpendicular to each other. Charge carrier Proton Electron Direction of q Same Opposite 3. Magnetic force of current carrying conductor  Current supplied to the conductor With F= B presence of current, thus use LeftHand rule

7.

Ampere’s law = For any closed path, the sum of the ∑ Δ 𝐵 = 𝜇𝑜 𝐼 product of the length elements, with the magnetic field parallel to the length elements, equals to , where I is the current enclosed by the closed path. = based on right hand grip rule Straight wire

∑ ∑(

= = B=

I𝓵

Cicular loop of N turns

∑ ∑(

= = B=

4.

5.

Magnetic flux density / magnetic field strength, B = force on a charge of one coulomb 𝑭 moving with a velocity of 1ms-1 at B= right angles to the magnetic field. 𝒒𝒗 = force on a a unit length conductor 𝑭 carrying a current of 1A at right B= angles to the field 𝑰𝓵 Moving charge in magnetic field = Moving of electron produced current. With presence of current, use Left-Hand rule to determine direction. = B, q and v must be perpendicular to each other.

F = Bqv =

𝒎 𝒗𝟐 𝒓

= mv 𝝎 = mr ω2, 𝝎 =

Long Solenoid of N turns

∑ ∑

=

Within solenoid:

B= At the end of solenoid:

B= 8.

Force between two current-carrying conductor Force acting on wire carrying I1 , F1 = B2I1

𝜇𝑜 𝐼2 )I 𝜋𝑑 1

𝟐𝝅

=(

𝑻

9.

6.

=

Motion of charged particle in magnetic and electric fields

Hall effect FE = FM qE = Bqv q ( = Bqv Hall voltage, V = B w v V = Bw ( = Bw (

V=

(

Direction of FE When FB = FE, FB = FE - Right-hand Bqv = qE Direction of FB Selected velocity, v = - Left-hand 10. Specific charge of ions,

mv2 = qV and Bqv =

𝒎 𝒗𝟐 𝒓