CLASS 10 SCIENCE - CHAPTER 11 NOTES
ELECTRICITY
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PAGE 1: ELECTRIC CURRENT & POTENTIAL DIFFERENCE
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[1.1] ELECTRIC CHARGE (Vidyut Aavesh)
* Properties of Charge: Charge do tarah ke hote hain—Positive (+) aur Negative (-).
Same charges ek doosre ko dur bhagate hain (repel) aur opposite charges attract karte
hain.
* SI Unit: Charge ki SI unit **Coulomb (C)** hoti hai.
* Electron Charge: Ek electron par 1.6 x 10^-19 C ka negative charge hota hai.
* Quantization Formula: **Q = ne**
(Jahan Q = Total charge, n = number of electrons, e = charge of one electron).
* Note: 1 Coulomb charge banane ke liye lagbhag 6.25 x 10^18 electrons milte hain.
[1.2] ELECTRIC CURRENT (Vidyut Dhara - I)
* Definition: Kisi conductor (wire) se per second behne waale electric charge ki
dar (rate of flow) ko Electric Current kehte hain.
* Formula: **I = Q / t** (Current = Charge / Time)
* SI Unit: Current ki SI unit **Ampere (A)** hoti hai.
* Measuring Instrument: Current ko naapne ke liye **Ammeter** ka use kiya jata hai.
Ise hamesha circuit mein **Series** (shreni kram) mein joda jata hai kyunki iska resistance
bohot kam hota hai.
* Direction: Electric current ki direction hamesha electrons ke behne ke ULTE
direction mein maani jaati hai (yaani Positive se Negative terminal ki taraf).
[1.3] ELECTRIC POTENTIAL & POTENTIAL DIFFERENCE (Vibhantar - V)
* Potential Difference: Kisi electric circuit mein ek unit charge ko ek point se
doosre point tak le jaane mein jo Kaam (Work done) kiya jata hai, use Potential Difference
kehte hain.
* Formula: **V = W / Q** (Potential Difference = Work done / Charge)
* SI Unit: Iski SI unit **Volt (V)** होती है ।
* Measuring Instrument: Ise naapne ke liye **Voltmeter** ka use kiya jata hai.
Ise hamesha circuit mein **Parallel** (parshv kram) mein joda jata hai kyunki iska
resistance bohot zyada hota hai.
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PAGE 2: OHM'S LAW & RESISTANCE
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[2.1] OHM'S LAW (Ohm ka Niyam) [Most Important]
* Statement: Agar kisi conductor ki physical conditions (jaise temperature) same rahein,
toh uske dono siron ke beech ka Potential Difference (V) usme behne waale
, Current (I) ke directly proportional hota hai.
* Expression: V ∝ I => **V = IR**
(Jahan 'R' ek constant hai jise Conductor ka Resistance kehte hain).
[DIAGRAM BRIEF: V-I GRAPH]
Ek X-axis par Current (I) aur Y-axis par Potential Difference (V) banayein.
Center (0) se ek bilkul seedhi tirchhi line (Straight line) upar ki taraf
khinchein. Yeh line 'R' (Resistance) ko darshati hai.
[2.2] RESISTANCE (Pratirodh - R)
* Definition: Kisi material ki wo property jo apne andar se current ke behne ka
virodh (oppose) karti hai, use Resistance kehte hain.
* Formula: **R = V / I**
* SI Unit: Iski SI unit **Ohm (Ω)** hoti hai.
[2.3] FACTORS ON WHICH RESISTANCE DEPENDS (R kin baaton par nirbhar karta hai)
Kisi wire ka resistance in 4 baaton par depend karta hai:
1. Length of Conductor: Resistance length ke directly proportional hota hai (R ∝ l). Wire jitna
lamba hoga, resistance utna zyada hoga.
2. Area of Cross-section: Resistance wire ki motai (Area) ke inversely proportional hota hai
(R ∝ 1/A). Wire jitna mota hoga, resistance utna kam hoga.
3. Nature of Material: Alag-alag metals ka resistance alag hota hai (jaise Silver sabse best
conductor hai).
4. Temperature: Temperature badhne se metals ka resistance badhta hai.
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PAGE 3: RESISTIVITY & COMBINATION OF RESISTORS (SERIES)
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[3.1] RESISTIVITY (Pratirodhakta - ρ)
* Jab hum factors ko jodte hain: R ∝ l/A => **R = ρ (l / A)**
(Jahan ρ - rho, ek constant hai jise Resistivity kehte hain).
* SI Unit: Resistivity ki SI unit **Ohm-meter (Ω-m)** hoti hai.
* Note: Resistivity wire ki lambai ya motai badalne se NAHI badalti. Yeh sirf material
aur temperature par depend karti hai. Alloys (mishra dhatu) ki resistivity pure metals
se bohot zyada hoti hai, isliye wo jaldi nahi jalte (jaise heater ka wire).
[3.2] COMBINATION OF RESISTORS (Pratirodhon ka Sanyojan)
Resistors ko do tarah se joda ja sakta hai: Series (Shreni) aur Parallel (Parshv).
A. SERIES COMBINATION (Shreni Kram)
* Isme resistors ko ek ke baad ek line se joda jata hai.
* Rules:
1. Har resistor mein **Current (I) SAME** rehta hai.
2. Potential Difference (V) alag-alag bat jata hai (V = V1 + V2 + V3).
* Derivation Formula:
V = V1 + V2 + V3
IR = IR1 + IR2 + IR3
ELECTRICITY
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PAGE 1: ELECTRIC CURRENT & POTENTIAL DIFFERENCE
--------------------------------------------------------------------------------
[1.1] ELECTRIC CHARGE (Vidyut Aavesh)
* Properties of Charge: Charge do tarah ke hote hain—Positive (+) aur Negative (-).
Same charges ek doosre ko dur bhagate hain (repel) aur opposite charges attract karte
hain.
* SI Unit: Charge ki SI unit **Coulomb (C)** hoti hai.
* Electron Charge: Ek electron par 1.6 x 10^-19 C ka negative charge hota hai.
* Quantization Formula: **Q = ne**
(Jahan Q = Total charge, n = number of electrons, e = charge of one electron).
* Note: 1 Coulomb charge banane ke liye lagbhag 6.25 x 10^18 electrons milte hain.
[1.2] ELECTRIC CURRENT (Vidyut Dhara - I)
* Definition: Kisi conductor (wire) se per second behne waale electric charge ki
dar (rate of flow) ko Electric Current kehte hain.
* Formula: **I = Q / t** (Current = Charge / Time)
* SI Unit: Current ki SI unit **Ampere (A)** hoti hai.
* Measuring Instrument: Current ko naapne ke liye **Ammeter** ka use kiya jata hai.
Ise hamesha circuit mein **Series** (shreni kram) mein joda jata hai kyunki iska resistance
bohot kam hota hai.
* Direction: Electric current ki direction hamesha electrons ke behne ke ULTE
direction mein maani jaati hai (yaani Positive se Negative terminal ki taraf).
[1.3] ELECTRIC POTENTIAL & POTENTIAL DIFFERENCE (Vibhantar - V)
* Potential Difference: Kisi electric circuit mein ek unit charge ko ek point se
doosre point tak le jaane mein jo Kaam (Work done) kiya jata hai, use Potential Difference
kehte hain.
* Formula: **V = W / Q** (Potential Difference = Work done / Charge)
* SI Unit: Iski SI unit **Volt (V)** होती है ।
* Measuring Instrument: Ise naapne ke liye **Voltmeter** ka use kiya jata hai.
Ise hamesha circuit mein **Parallel** (parshv kram) mein joda jata hai kyunki iska
resistance bohot zyada hota hai.
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PAGE 2: OHM'S LAW & RESISTANCE
--------------------------------------------------------------------------------
[2.1] OHM'S LAW (Ohm ka Niyam) [Most Important]
* Statement: Agar kisi conductor ki physical conditions (jaise temperature) same rahein,
toh uske dono siron ke beech ka Potential Difference (V) usme behne waale
, Current (I) ke directly proportional hota hai.
* Expression: V ∝ I => **V = IR**
(Jahan 'R' ek constant hai jise Conductor ka Resistance kehte hain).
[DIAGRAM BRIEF: V-I GRAPH]
Ek X-axis par Current (I) aur Y-axis par Potential Difference (V) banayein.
Center (0) se ek bilkul seedhi tirchhi line (Straight line) upar ki taraf
khinchein. Yeh line 'R' (Resistance) ko darshati hai.
[2.2] RESISTANCE (Pratirodh - R)
* Definition: Kisi material ki wo property jo apne andar se current ke behne ka
virodh (oppose) karti hai, use Resistance kehte hain.
* Formula: **R = V / I**
* SI Unit: Iski SI unit **Ohm (Ω)** hoti hai.
[2.3] FACTORS ON WHICH RESISTANCE DEPENDS (R kin baaton par nirbhar karta hai)
Kisi wire ka resistance in 4 baaton par depend karta hai:
1. Length of Conductor: Resistance length ke directly proportional hota hai (R ∝ l). Wire jitna
lamba hoga, resistance utna zyada hoga.
2. Area of Cross-section: Resistance wire ki motai (Area) ke inversely proportional hota hai
(R ∝ 1/A). Wire jitna mota hoga, resistance utna kam hoga.
3. Nature of Material: Alag-alag metals ka resistance alag hota hai (jaise Silver sabse best
conductor hai).
4. Temperature: Temperature badhne se metals ka resistance badhta hai.
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PAGE 3: RESISTIVITY & COMBINATION OF RESISTORS (SERIES)
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[3.1] RESISTIVITY (Pratirodhakta - ρ)
* Jab hum factors ko jodte hain: R ∝ l/A => **R = ρ (l / A)**
(Jahan ρ - rho, ek constant hai jise Resistivity kehte hain).
* SI Unit: Resistivity ki SI unit **Ohm-meter (Ω-m)** hoti hai.
* Note: Resistivity wire ki lambai ya motai badalne se NAHI badalti. Yeh sirf material
aur temperature par depend karti hai. Alloys (mishra dhatu) ki resistivity pure metals
se bohot zyada hoti hai, isliye wo jaldi nahi jalte (jaise heater ka wire).
[3.2] COMBINATION OF RESISTORS (Pratirodhon ka Sanyojan)
Resistors ko do tarah se joda ja sakta hai: Series (Shreni) aur Parallel (Parshv).
A. SERIES COMBINATION (Shreni Kram)
* Isme resistors ko ek ke baad ek line se joda jata hai.
* Rules:
1. Har resistor mein **Current (I) SAME** rehta hai.
2. Potential Difference (V) alag-alag bat jata hai (V = V1 + V2 + V3).
* Derivation Formula:
V = V1 + V2 + V3
IR = IR1 + IR2 + IR3
