Pressure Cooker Jaldi Kyun Pakata Hai?
Cooker ka asli jaadu hai band bhaap ka dabav. Dabav badhta hai toh paani 100°C pe nahi, lagbhag 120°C pe ubalta hai, aur zyada garam paani khana jaldi gala deta hai 🍲
📖 Kahani: “Teen Seeti ka Raaz”
Ravivaar ki shaam thi. Priya ke ghar Golu aur Rohan homework karne aaye the. Rasoi se aawaaz aayi: “Seeeee!” Priya ki mummy ne kaha, “Bas, do seeti aur, phir rajma tayyar!”
Golu chaunk gaya: “Aunty, kal hamare ghar ki gas khatam ho gayi thi. Mummy ne padosi ke chulhe pe khule pateele mein rajma banaye, toh ghanton lag gaye! Aur aapke cooker mein itni jaldi?”
Rohan ne turant theory di: “Simple hai! Cooker mein aag zyada lagti hogi, ya cooker ki steel special hoti hogi.”
Priya soch mein pad gayi: “Par gas toh wahi hai, aanch bhi wahi. Aur yeh seeti baar-baar kyun bajti hai? Kya seeti hi khana pakati hai?”
Teeno doorway pe khade cooker ko ghoor rahe the, jaise woh koi jaadu ka dabba ho. Chalo, aaj is “jaadu ke dabbe” ka science kholte hain! 🔍
✅ Seedha Jawab
Khule bartan mein paani lagbhag 100°C pe ubalta hai, aur us se zyada garam ho hi nahi paata. Cooker ka dhakkan bhaap ko andar band kar deta hai, toh andar dabav (pressure) lagbhag do guna ho jaata hai. Zyada dabav mein paani ko ubalne ke liye zyada garmi chahiye, isliye woh lagbhag 120°C pe ubalta hai. Itne garam paani aur bhaap mein dal, chawal, aalu bahut jaldi gal jaate hain. Seeti bas extra bhaap bahar nikaal ke dabav ko ek had mein rakhti hai.
🤔 Kyun? Step-by-Step
Kachchi dal, chawal ya aalu ke andar starch ke daane aur sakht deewaron wali koshikayein (cells) hoti hain. Garam paani andar ghus ke starch ko phulata hai aur deewaron ko naram karta hai. Tab khana gal jaata hai.
Kyun taapmaan itna zaroori hai? Yeh badlaav garmi se hota hai. Jitna zyada garam paani, utni tezi se yeh kaam hota hai. Mota-mota niyam: taapmaan lagbhag 10°C badhe toh aise bahut se badlaav lagbhag do guna jaldi hote hain.
Gas jalao, paani garam hota jaata hai: 40, 60, 80… aur lagbhag 100°C pe ubalne lagta hai. Ab aanch kitni bhi tez karo, paani ka taapmaan 100°C ke aas-paas hi rehta hai. Extra garmi bas aur zyada bhaap banane mein chali jaati hai.
Kyun? Ubalte waqt paani ke kan garmi le ke bhaap ban ke ud jaate hain. Garmi paani mein “jama” nahi hoti, bhaap ke saath bahar nikal jaati hai. Isi liye khule pateele mein rajma ghanton lete hain.
Paani ki satah pe hamesha upar se hawa ka dabav padta rehta hai, jaise koi halke se dhakkan daba ke rakhe. Paani ke kanon ko bhaap ban ke udne ke liye is dabav ko dhakelna padta hai. Samundar ke kinaare ya maidaan mein yeh dabav itna hai ki paani 100°C pe ubalta hai.
Kyun dabav se farak padta hai? Dabav zyada = kanon ko bahar nikalne ke liye zyada “zor” (zyada garmi) chahiye = ubalne ka taapmaan zyada. Dabav kam = kam garmi mein hi nikal jaate hain = ubalne ka taapmaan kam.
Cooker ka dhakkan rubber ki ring (gasket) ke saath ekdum tight band hota hai. Ab jo bhaap banti hai woh bahar nahi jaa paati, andar hi jama hoti jaati hai. Jitni zyada bhaap, utna zyada dabav. Normal ghar ke cooker mein andar ka dabav bahar ki hawa se lagbhag do guna tak pahunch jaata hai.
Kyun ring zaroori? Agar kinaare se bhaap “sss” karke leak ho, toh dabav banega hi nahi, aur cooker ek saadharan pateela ban jaayega.
Do guna dabav mein paani lagbhag 120°C tak garam ho jaata hai tab ubalta hai. Ab dal aur rajma 100°C nahi, 120°C ke paani aur bhaap mein pak rahe hain. Step 1 ka niyam yaad karo: lagbhag 20°C zyada garmi matlab kaam kai guna tez!
Kyun gas bhi bachti hai? Kam samay tak chulha jalta hai, aur bhaap bahar nahi udti, toh garmi aur paani dono kam barbaad hote hain.
Dhakkan ke beech ek patli nali hoti hai jis pe ek bhaari seeti (wazan) rakha hota hai. Jab andar ka dabav ek had se zyada ho jaata hai, toh bhaap seeti ko upar utha deti hai, thodi bhaap “seeee!” karke bahar nikalti hai, aur seeti wapas baith jaati hai. Iske alawa ek safety valve bhi hota hai: agar seeti wali nali band ho jaaye aur dabav khatarnaak had tak badhe, toh woh khul ke bhaap nikaal deta hai.
Kyun? Bina rok-tok dabav badhta rahe toh cooker phat sakta hai. Seeti dabav ko lagbhag ek jaisa rakhti hai, isliye taapmaan bhi lagbhag 120°C pe tika rehta hai. Seeti khana nahi pakati, sirf suraksha aur santulan rakhti hai.
Ek line mein: Dhakkan band → bhaap andar → dabav ~2 guna → paani ~120°C pe ubalta → khana jaldi galta → seeti extra bhaap nikaalti. 🍲⏱️
🖼️ Picture se Samjho
📕 Textbook Yeh Nahi Batata
1. Cooker 340 saal se bhi purana idea hai! Saal 1679 mein France ke ek scientist Denis Papin ne ek band, mazboot bartan banaya jise “steam digester” kaha gaya. Usmein bhaap ke dabav se haddiyan tak naram ho jaati thi. Dabav se bartan phat na jaaye, isliye usne usmein ek safety valve bhi lagaya. Aaj ka aapka cooker usi idea ka desi, chhota roop hai!
2. Hospital ka “bada cooker”. Hospital aur labs mein auzaar (instruments) saaf karne ke liye ek machine hoti hai: autoclave. Woh bhi dabav wali bhaap se kaam karti hai, lagbhag 121°C pe. Itni garam bhaap mein woh keetanu bhi khatam ho jaate hain jo saadharan ubalte paani mein bach sakte hain.
3. Everest pe chai “thandi” ubalti hai! Duniya ki sabse oonchi choti pe hawa ka dabav bahut kam hota hai, toh wahan paani sirf lagbhag 70°C pe ubal jaata hai. Paani ubal raha hai, par itna garam nahi ki dal-chawal theek se gal sakein. Isi liye pahad pe rehne wale aur parvatarohi pressure cooker zaroor rakhte hain. 🏔️
🚫 Log Aisa Sochte Hain… Lekin
✅ Lekin: gas aur aanch toh wahi hai. Farak dabav ka hai: band bhaap ki wajah se andar ka paani 100°C ki jagah lagbhag 120°C tak garam ho paata hai.
✅ Lekin: ubalta paani lagbhag 100°C pe hi atka rehta hai. Tez aanch se bas bhaap zyada banti hai aur gas zyada kharch hoti hai, khana utna hi time leta hai.
✅ Lekin: seeti sirf extra bhaap bahar nikaalti hai. Khana andar ke garam paani aur bhaap se pakta hai. Har seeti ke saath thoda paani bhaap ban ke nikal jaata hai, toh zaroorat se zyada seeti se paani kam hoke khana neeche chipak ya jal sakta hai.
✅ Lekin: pahad pe paani jaldi ubalta zaroor hai, par kam taapmaan pe (jaise Leh mein lagbhag 88°C). Kam garam paani mein khana der se pakta hai.
🏠 Ghar ka Mini Experiment: “Aalu Race” (bade ke saath)
Is experiment mein chulha aur cooker sirf ghar ke bade chalayenge. Aap scientist ho: aapka kaam hai ghadi dekhna, note karna aur nateeja nikaalna.
Saamaan: 2 aalu ke lagbhag barabar size ke tukde (bade kaatenge), ek khula pateela, ghar ka pressure cooker, paani, phone ya ghadi ka stopwatch, copy-pen, ek chammach aur do plate.
Kya seekha aur kyun: Pateele wala aalu shayad abhi bhi beech se sakht hoga, aur cooker wala naram. Pateele mein paani 100°C pe atka raha, jabki cooker mein band bhaap ke dabav se paani aur bhaap lagbhag 120°C tak pahunche. (Dhyaan do: gas band hone ke baad bhi cooker kuch der garam rehta hai aur andar khana thoda pakta rehta hai. Yeh bhi cooker ki garmi bachane ki khoobi hai!) Sabak: zyada dabav → zyada taapmaan → jaldi pakna!
🌍 Real Life Mein
- Pahadon ki rasoi: Leh, Ladakh ya oonche pahadi ilaakon mein paani 100°C se kaafi kam pe ubalta hai, isliye wahan dal-chawal ke liye pressure cooker lagbhag zaroori hai. Oonchi jagahon pe tainaat jawaanon ki rasoi mein bhi cooker kaam aata hai.
- Gas aur samay ki bachat: cooker mein khana jaldi pakta hai aur bhaap kam udti hai, toh LPG kam lagti hai. Isi liye Indian rasoi mein lagbhag har ghar mein cooker milta hai.
- Rajma-chhole raat bhar bhigona: bhigone se daane pehle hi paani sokh lete hain, toh cooker mein aur bhi jaldi galte hain. Garmi + paani + dabav, teeno milke kaam karte hain.
- Car ka radiator: gaadi ka engine thanda rakhne wala paani ek band, dabav wale system mein rehta hai. Dabav ki wajah se woh 100°C pe nahi ubalta, aur engine ko achhe se thanda rakh paata hai. (Isi liye garam engine ka radiator dhakkan kabhi nahi kholte.)
- Hospital ka autoclave: dabav wali, lagbhag 121°C ki bhaap se auzaar keetanu-mukt kiye jaate hain, bilkul ek bade, mazboot cooker ki tarah.
🔗 NCERT Connection
Yeh topic Class 8 Science (Curiosity) ke in chapters se judta hai:
- Chapter 6: Pressure, Winds, Storms, and Cyclones: dabav kya hota hai, aur gas (jaise bhaap ya hawa) bhi apne bartan ki deewaron pe dabav daalti hai. (CharuMam pe jald)
- Chapter 7: Particulate Nature of Matter: paani ke kan garmi paa ke tez hilte hain aur ubal ke bhaap bante hain; drav se gas mein badlaav. (CharuMam pe jald)
Saare chapters ki list: Class 8 Science (CharuMam)
📝 Recap
- Khana garmi se pakta hai; zyada taapmaan = jaldi pakna.
- Khule bartan mein paani lagbhag 100°C pe ubalta hai, aur tez aanch se bhi us se zyada garam nahi hota.
- Ubalne ka taapmaan dabav pe nirbhar hai: dabav zyada → ubalne ka taapmaan zyada; dabav kam → kam.
- Cooker ka dhakkan aur rubber ring bhaap ko band karte hain, toh andar dabav lagbhag 2 guna aur paani lagbhag 120°C ho jaata hai.
- Seeti extra bhaap nikaal ke dabav ko had mein rakhti hai; safety valve khatre ke waqt bachaata hai.
- Pahad pe dabav kam, paani kam taapmaan pe ubalta hai, isliye wahan cooker aur bhi kaam ka hai.
🎯 Quiz (5 MCQ)
1. Pressure cooker mein khana jaldi kyun pakta hai? (a) Cooker ki steel khaane ko zyada garmi deti hai (b) Andar dabav badhne se paani lagbhag 120°C pe ubalta hai, aur zyada garam paani khana jaldi galata hai (c) Seeti ki aawaaz khaane ko naram karti hai (d) Cooker mein paani kam hota hai, isliye
✅ (b): band bhaap dabav badhati hai, jis se ubalne ka taapmaan badh jaata hai. (a) Galat: steel sirf garmi aage pahunchati hai, extra garmi nahi banati; gas wahi hai. (c) Galat: seeti sirf bhaap nikalne ki aawaaz hai. (d) Galat: kam paani se khana jaldi nahi, balki jalne ka khatra hota hai.
2. Khule pateele mein paani ubal raha hai. Aanch aur tez kar di. Ab paani ka taapmaan? (a) Lagbhag 150°C tak chala jaayega (b) Kam ho jaayega (c) Lagbhag 100°C pe hi rahega, bas bhaap zyada banegi (d) Turant 120°C ho jaayega
✅ (c): ubalte waqt extra garmi bhaap banane mein lagti hai, taapmaan lagbhag 100°C pe atka rehta hai. (a) Galat: khule bartan mein paani 100°C se upar nahi jaata. (b) Galat: tez aanch se taapmaan kam nahi hota. (d) Galat: 120°C ke liye dabav chahiye, jo band cooker mein banta hai, khule pateele mein nahi.
3. Leh jaise oonche pahad pe paani lagbhag kitne °C pe ubalta hai, aur wahan khule bartan mein dal? (a) Lagbhag 88°C; dal der se pakti hai (b) 100°C; dal utne hi time mein pakti hai (c) Lagbhag 120°C; dal jaldi pakti hai (d) Lagbhag 88°C; dal jaldi pakti hai
✅ (a): pahad pe hawa ka dabav kam hai, toh paani kam taapmaan pe ubalta hai, aur kam garam paani mein dal der se galti hai. (b) Galat: 100°C sirf maidaan jaise normal dabav pe hota hai. (c) Galat: 120°C toh cooker ke andar ke zyada dabav pe hota hai. (d) Galat: taapmaan sahi hai par nateeja ulta hai; kam taapmaan = der se pakna.
4. Cooker ki seeti ka asli kaam kya hai? (a) Khana pakana (b) Cooker ke andar hawa bhejna (c) Gas apne aap band karna (d) Had se zyada dabav hone pe thodi bhaap bahar nikaal ke dabav ko had mein rakhna
✅ (d): seeti ek wazan hai jo zyada dabav pe uthti hai aur extra bhaap nikaal deti hai. (a) Galat: khana garam paani aur bhaap se pakta hai. (b) Galat: seeti se bhaap bahar jaati hai, hawa andar nahi aati. (c) Galat: seeti ka gas se koi connection nahi; gas insaan band karta hai.
5. Cooker ke dhakkan ki rubber ring (gasket) dheeli ho jaaye toh kya hoga? (a) Khana aur jaldi pakega (b) Kinaare se bhaap leak hogi, dabav nahi banega aur khana der se pakega (c) Seeti zyada baar bajegi (d) Kuch farak nahi padega
✅ (b): ring ka kaam bhaap ko andar rokna hai; leak hone pe dabav aur taapmaan nahi badhte. (a) Galat: leak se dabav ghatta hai, toh pakna dheema hota hai. (c) Galat: bhaap kinaare se nikal jaayegi, toh dabav seeti uthane layak hi nahi banega aur seeti kam ya bilkul nahi bajegi. (d) Galat: ring hi cooker ko “band” banati hai.
🧠 Socho aur Batao
1. Rohan ne kaha: “Seeti jaldi aaye, isliye cooker mein bas ek chammach paani daal do, khana aur jaldi pakega!” Kya Rohan sahi hai?
Nahi. Dabav aur taapmaan bhaap se bante hain, aur bhaap paani se banti hai. Bahut kam paani jaldi khatam ho jaayega: na khana theek se pakega, na barabar bhaap rahegi, aur neeche khana chipak ke jal sakta hai. Khaali hote cooker ko garam karte rehna khatarnaak bhi hai. Isliye hamesha cooker ki booklet ya recipe ke hisaab se sahi maatra mein paani daalna chahiye.
2. Priya ne socha: “Agar cooker ke andar dabav aur zyada, jaise 5 guna, kar dein toh khana pal bhar mein pak jaayega!” Isme kya dikkat hai?
Science ke hisaab se zyada dabav pe paani aur zyada garam hota, haan. Par ghar ka cooker itne dabav ke liye bana hi nahi hai. Usmein seeti aur safety valve isi liye hain ki dabav ek surakshit had se upar na jaaye. Had se zyada dabav mein bartan phat sakta hai. Sabak: science mein “zyada” hamesha “behtar” nahi hota; sahi maatra aur suraksha dono zaroori hain.
❓ FAQ
1. Cooker kholne se pehle intezaar kyun karte hain?
Gas band karne ke baad bhi andar dabav aur 100°C se zyada garam paani hota hai. Agar dabav rehte dhakkan khul jaaye, toh dabav ekdum gir jaata hai aur woh garam paani ek jhatke mein ubal ke bahar uchhal sakta hai, jis se bura jal sakte hain. Isi liye bade cooker ko apne aap thanda hone dete hain aur dhakkan bina zor lagaye khulne tak intezaar karte hain. Bachchon ko cooker kholna hi nahi chahiye.
2. Pehli seeti ke baad aanch dheemi kyun kar dete hain?
Jab dabav ban gaya, toh andar ka taapmaan lagbhag 120°C pe tika rehta hai. Tez aanch se taapmaan aur nahi badhta, bas zyada bhaap seeti se bahar nikalti hai: gas bhi barbaad aur paani bhi kam. Dheemi aanch dabav ko banaye rakhne ke liye kaafi hoti hai.
3. Cooker ko oopar tak kyun nahi bharte?
Bhaap aur dabav banne ke liye andar khaali jagah chahiye. Dal, chawal jaisi cheezein ubalte waqt jhaag banati hain; agar cooker bahut bhara ho toh jhaag ya khaane ke daane seeti wali nali tak pahunch ke use band kar sakte hain. Isliye cooker ki booklet mein likhi had (jaise “itne se zyada mat bharo”) ka dhyaan rakha jaata hai.
💖 CharuMam Motivation
Cooker humein ek pyaari baat sikhaata hai: thoda dabav kaam ki cheez hai. Usi dabav se kachchi, sakht dal naram aur swaadisht ban jaati hai. Exam, competition, naye sawaal: in sab ka thoda dabav aapko bhi “pakaata” hai, aapko mazboot aur tayyar banata hai.
Par yaad rakhna beta, cooker mein seeti aur safety valve bhi hote hain. Jab dabav zyada lage, toh apni “seeti” bajao: mummy-papa, teacher ya dost se baat karo, thoda khelo, achhi neend lo. Dabav ko andar band karke mat rakho. Sahi dabav + sahi seeti = perfect pakki hui kaamyaabi! 🍲✨
— CharuMam
Koi doubt? CharuMam AI Tutor se poochho! 💬
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