Class 6 Science · Chapter 5
Short answer: Ye chapter lambai measure karne ke sahi tareeke (SI units, zero error, parallax error se bachna) aur motion ke 3 types — rectilinear, circular, periodic — sikhata hai, saath hi speed ka basic formula (Distance/Time) bhi cover karta hai.
Class 6 Science Curiosity chapter 5, "Measurement of Length and Motion", us bunyaadi skill ki neev hai jispe aage ka poora physics chapter khada hota hai — chahe woh Class 7 ka Temperature ho ya Class 9 ka Motion. Ye chapter sikhata hai ki koi bhi cheez ko sahi tarike se kaise measure karte hain, aur motion ko kaise categorize karte hain — rectilinear, circular aur periodic. Agar tum NCERT Class 6 Science Curiosity chapter wise notes bana rahe ho, to is chapter ko carefully samajhna zaroori hai kyunki ye SI units aur measurement skills baaki sab chapters (jaise Temperature and its Measurement) me bhi kaam aayenge.
Ye chapter class 6 science Curiosity book vs old NCERT syllabus ke context me bhi important hai — pehle ye concepts bikhre hue the, ab ek focused chapter me integrate kiye gaye hain jo 2026-27 ke rationalised syllabus ka hissa hai.
Chapter 5 Summary — 5 Minute Revision
Chapter 5 "Measurement of Length and Motion" ke core takeaways: (1) Lambai ka SI unit metre hai, aur conversions (km, m, cm, mm) yaad rakhna zaroori hai. (2) Sahi measurement ke liye zero error aur parallax error se bachna chahiye — scale ka 0 mark object ke sire se align karo aur eye ko perpendicular rakho. (3) Motion teen tarah ki hoti hai — rectilinear (seedhi line), circular (fixed point ke around), aur periodic/oscillatory (fixed interval me repeat hone waali, jaise pendulum). (4) Speed = Distance/Time, aur km/h ko m/s me convert karne ke liye (5/18) factor use hota hai. Ye foundational concepts aage Temperature and its Measurement class 6 NCERT solutions jaise chapters aur higher classes ke physics ke liye base banate hain.
In-Text Questions — Solutions
Ek scale se lambai naapte waqt eye ki position kaisi honi chahiye?
Eye ko measurement point ke exactly seedha (perpendicular) rakhna chahiye, warna parallax error aa jaata hai aur reading galat mil sakti hai — thodi tirchi nazar se dekhne par object choti ya badi dikh sakti hai.Rectilinear motion aur circular motion me kya farak hai?
Rectilinear motion me object seedhi line me chalta hai (jaise straight road pe car), jabki circular motion me object ek fixed point ke around, fixed distance banaye rakhte hue ghoomta hai (jaise ceiling fan ke blades ya ghadi ki suiyaan).Periodic motion ka ek real-life example do.
Simple pendulum ka jhoolna periodic motion ka classic example hai — ye fixed time interval baad apni motion repeat karta hai. Doosra example: ghadi ki second-hand ka circular movement bhi periodic hai kyunki wo bhi fixed time me repeat hoti hai.Exercise Questions — Solutions (Q1–Q6)
1. 1 metre me kitne centimetre hote hain?
Solution:
1 m = 100 cm
Isliye 1 metre me 100 centimetre hote hain. Yaad rakho — SI system me lambai ka mool (base) unit metre (m) hai, aur baaki units (cm, mm, km) isi se derive hote hain.
2. Ek pencil ki lambai 12.4 cm napi gayi. Ise metre me convert karo.
Solution:
Length = 12.4 cm
1 cm = 1/100 m
12.4 cm = 12.4 × (1/100) m = 0.124 m
Pencil ki lambai = 0.124 m
3. Ek car 2 ghante me 120 km ki doori tay karti hai. Uski average speed nikaalo km/h aur m/s dono me.
Solution:
Distance = 120 km, Time = 2 h
Speed = Distance/Time = 120/2 = 60 km/h
Ab m/s me convert karte hain:
60 km/h = 60 × 1000 m / 3600 s = 60000/3600 = 16.67 m/s
Average speed = 60 km/h ya 16.67 m/s (approx)
4. Bataao kaunsi motion rectilinear hai, kaunsi circular, aur kaunsi periodic — (a) fan ke blades ka ghoomna (b) train ka straight track pe chalna (c) pendulum ka jhoolna.
Solution:
- (a) Fan ke blades ka ghoomna — Circular motion (ek fixed point ke around ghoomta hai)
- (b) Train ka straight track pe chalna — Rectilinear motion (seedhi line me)
- (c) Pendulum ka jhoolna — Periodic motion (fixed time interval me repeat hoti hai; ye oscillatory bhi hai)
5. Simple pendulum banane ke liye kaunsa apparatus chahiye aur oscillation kya hoti hai, explain karo.
Solution:
Apparatus: ek dhaaga (thread), ek bob (chhota bhaari weight jaise metal ka gola), aur ek clamp stand jispe dhaaga baandha jaata hai.
Jab bob ko ek side se chhoda jaata hai, woh mean position (beech ki position) ke around aage-peeche jhoolta hai. Oscillation uss poori motion ko kehte hain jisme bob mean position se ek extreme tak jaaye, wapas mean se hote hue doosre extreme tak jaaye, aur phir mean position pe wapas aa jaaye — yani ek complete to-and-fro movement.
6. Kisi measurement me zero error kya hota hai aur ise kaise avoid karte hain?
Solution:
Zero error tab hota hai jab measuring instrument (jaise scale) ka zero mark object ke ek sire (end) se exactly align nahi hota — ya to gap reh jaata hai ya overlap ho jaata hai, jisse reading galat aa jaati hai.
Isse avoid karne ke liye: object ke ek sire ko scale ke 0 mark se sahi tarah align karo, eye ko measurement point ke seedha (perpendicular) rakho (parallax error se bachne ke liye), aur agar 0 mark ghisa hua ho to kisi doosre poore number (jaise 1 cm mark) se start karke aakhir me subtract kar do.
Important Equations — Ek Nazar Me
| Concept | Formula / Rule |
|---|---|
| SI unit of length | Metre (m) |
| Length conversions | 1 km = 1000 m | 1 m = 100 cm | 1 cm = 10 mm |
| Speed | Speed = Distance / Time |
| Unit conversion (km/h to m/s) | km/h × (5/18) = m/s |
| Unit conversion (m/s to km/h) | m/s × (18/5) = km/h |
| Types of motion | Rectilinear (seedhi line), Circular (fixed point ke around), Periodic/Oscillatory (fixed interval me repeat) |
↔ Table ko side me swipe karein
Common Mistakes — Yahan Marks Kat te Hain
- Length measure karte waqt scale ka zero mark object ke sire se align na karna — isse zero error aa jaata hai aur poora answer galat ho jaata hai.
- Eye ko measurement point ke seedha na rakhna — tirchi nazar se dekhne se parallax error aata hai jo reading ko galat bana deta hai.
- Speed calculate karte waqt units mix kar dena — jaise distance km me aur time seconds me rakhkar directly divide kar dena, bina proper conversion kiye.
- Circular motion aur periodic motion ko same samajh lena — har circular motion periodic ho sakti hai, par har periodic motion circular nahi hoti (jaise pendulum periodic hai lekin uska path circular nahi, arc-shaped hai).
- km/h ko m/s me convert karte waqt factor (5/18) ki jagah galti se (18/5) laga dena ya vice versa.
- Oscillation ki definition incomplete likhna — sirf 'ek taraf jaana' likh dena, jabki oscillation ka matlab hai mean se ek extreme, wapas mean, phir doosre extreme, aur wapas mean tak ka poora to-and-fro cycle.
Board-Style Important Questions
- Class 6 school-level assessments me is chapter se length ki units convert karne wale numericals (km→m→cm→mm) practice ke liye zaroor try karo.
- Speed calculate karne wale word problems (distance aur time diye ho, speed nikaalni ho, ya vice versa) is chapter ka common question-type hai.
- Rectilinear, circular aur periodic motion ke real-life examples classify karne wale questions frequently practice karaye jaate hain — jaise train, fan, pendulum, ghadi ki suiyaan.
- Zero error aur parallax error se bachne ke correct measurement steps likhna bhi ek common short-answer type question hai.
- Simple pendulum ki activity based questions — oscillation define karo, ya diagram bana kar mean position aur extreme positions batao — school tests me aate hain.
- Note: Yahan koi specific exam year, board paper code, ya official marks-weightage claim nahi diya gaya hai kyunki wo verified officially available nahi hai — practice ke liye apne school ke sample papers aur NCERT exemplar dekho.
Aksar Poochhe Jaane Wale Sawaal
Class 6 Science Curiosity chapter 5 'Measurement of Length and Motion' me kya-kya topics cover hote hain?
Is chapter me lambai measure karne ke tareeke, SI units (metre aur uske multiples/sub-multiples), sahi measurement ke liye precautions (zero error, parallax error), aur motion ke types — rectilinear, circular, aur periodic/oscillatory motion — cover hote hain. Speed ka basic concept bhi introduce hota hai.
NCERT Class 6 Science Curiosity chapter wise notes kahan se best milte hain?
Sabse reliable tareeka hai NCERT ka apna textbook PDF (ncert.nic.in) padhna aur uske saath in-text activities khud try karna. Chapter-wise summary notes revision ke liye useful hote hain, par concept clarity ke liye original textbook ke activities aur figures dekhna zaroori hai — khaaskar measurement wale chapters me jahan practical observation matter karta hai.
Measurement of Length and Motion class 6 numericals solve karne ka best tareeka kya hai?
Pehle units clearly note karo (km, m, cm, mm), phir conversion factor yaad karo (1 km = 1000 m, 1 m = 100 cm, 1 cm = 10 mm). Speed wale numericals me formula Speed = Distance/Time use karo aur answer ko dono common units (km/h aur m/s) me likhne ki practice karo, kyunki exam me kabhi bhi ek unit maang sakte hain.
Kya is chapter me measurement ke saath koi practical activity bhi hai?
Haan, textbook me students ko khud alag-alag objects (jaise kitab, pencil, table) ki lambai scale se naapne ko kaha jaata hai, aur simple pendulum banakar uski oscillations count karne ki activity bhi di jaati hai. Ye hands-on activities concept ko practically samajhne me help karti hain, isliye inhe skip mat karo.
class 6 science Curiosity book vs old NCERT syllabus me kya farak hai?
Purani NCERT Science book me measurement aur motion ka topic alag chapters me bikhra hua tha aur kuch physics concepts Class 7-8 me shift kiye gaye the. Curiosity book (2026-27 rationalised syllabus) me ye topics ek focused chapter me integrated kiye gaye hain jisme measurement skills aur basic motion concepts ek saath introduce hote hain — foundational approach zyada hai.
NCERT Class 6 Science Curiosity 2026-27 syllabus PDF kahan se download karein?
Official aur sabse reliable source ncert.nic.in hai, jahan se current rationalised syllabus aur textbook dono PDF format me free download ho sakte hain. Kisi bhi third-party aggregator se pehle official NCERT site check karna behtar hai taaki syllabus current session ke hisaab se verified ho.
Class 6 Science — Saare Chapters
NCERT Kaksha ek swatantra shaikshik platform hai aur NCERT ya CBSE se aadhikarik roop se sambaddh (officially affiliated) nahi hai. Kisi galti ki jaankari dene ke liye contact kijiye.