Simple pendulum kya hai?

Simple pendulum ke hisse

Simple pendulum ek chhoti dhaatu ki gend hai, jise bob kehte hain, jo lambe dhaage se ek mazboot support se latki ho. Jab bob seedha neeche ruka latakta hai, to wo apni mean position (O) pe hota hai. Bob ko thoda ek taraf le jaakar chhodo: wo aage-peeche jhoolne lagta hai. Ye gati periodic hai, kyunki bob ek tay samay ke baad apna raasta dohraata hai. Ye wahi oscillatory motion hai jo Class 6 mein dhaage pe latke rubber ke jhoolne mein dekhi thi.

Ek oscillation aur time period

Jhoole ke sabse door ke points extreme positions A aur B hain. Bob ek oscillation tab poora karta hai jab wo O se shuru hokar A tak jaaye, mude, B tak jhoole, phir mude aur waapas O pe aaye. A se B aur waapas A jaana bhi ek oscillation hai. Ek oscillation mein laga time pendulum ka time period hai.

Khud naapo

Lagbhag 150 cm lambi dori se ek bhaari gend ya pathar baandho, aur dori ko mazboot support se aise baandho ki support aur bob ke beech lagbhag 100 cm latke. Bob ke rukne ka intezaar karo, phir use thoda ek taraf le jaakar bina dhakka diye, dori kasi rakhte hue, dheere se chhodo. Ghadi se 10 oscillations ka time naapo, 3 ya 4 baar dohraao, aur har time ko 10 se bhaag do.

Trial	10 oscillations ka time → time period (sample)
1	20.1 s → 2.01 s
2	19.9 s → 1.99 s
3	20.0 s → 2.00 s

Time period har baar lagbhag ek jaisa aata hai. Tumhari readings in sample values se thodi alag ho sakti hain, par aapas mein kaafi milti-julti honi chahiye.

Time period kya badalta hai?

Scientist ki tarah socho aur ek baar mein ek hi cheez badlo. Wahi bob rakho aur do-teen alag lambai ke dhaage lagaao: pendulum jitna lamba, time period utna lamba. Phir lambai tay rakho aur bob halka ya bhaari karo: time period wahi rehta hai. Isliye simple pendulum ka time period uski lambai pe depend karta hai, bob ke mass pe nahi, aur ek jagah pe ek jaisi lambai ke saare pendulums ka time period ek jaisa hota hai. (Extra: picture ki sample values, 25 cm ke liye lagbhag 1.0 s, 50 cm ke liye 1.4 s aur 100 cm ke liye 2.0 s, dikhati hain ki pendulum chaar guna lamba karne se time period dugna hota hai.)

Galileo aur Huygens

Kaha jaata hai ki Galileo Galilei (1564–1642) ne church mein baithe hue ek latakte lamp ko aage-peeche jhoolte dekha. Apni nabz ko timer bana kar unhone paaya ki har jhoola utna hi time leta hai. Alag-alag pendulums ke saath prayog karke unhone nishkarsh nikaala ki tay lambai ka pendulum ek oscillation mein hamesha utna hi time leta hai. Isse prerit hokar Christiaan Huygens (1629–1695) ne 1656 mein pendulum clock banaaya aur 1657 mein uska patent liya.

Ye kyun zaroori hai

Kyunki tay lambai ke pendulum ka time period constant rehta hai, uske jhoole barabar samay ke antar gin sakte hain, jo har clock ka buniyaadi vichaar hai. Yahi vigyaan playground ke jhoole mein bhi dikhta hai, jiska time period bhi uski lambai pe depend karta hai. Clocks ke itihaas mein pendulum ki jagah time kaise naapte hain mein padho. Textbook ke sawaalon ke jawab Chapter 8 ke NCERT solutions mein hain; poore chapter ke liye Chapter 8 ke notes.