Measurement of Length and Motion Class 6 (Curiosity)

(Page 97) Some lengths are given in Column I of Table . Some units are given in Column II. Match the lengths with the units suitable for measuring those lengths.

(Page 97) Read the following statements and mark True (T) or False (F) against each. (i) The motion of a car moving on a straight road is an example of linear motion. True
The car is moving in a straight line which is an example of linear motion

(Page 97) Read the following statements and mark True (T) or False (F) against each. (ii) Any object which is changing its position with respect to a reference point with time is said to be in motion. True
The athlete is changing its position with respect to the reference point
So Athlete is in motion

(Page 97) Read the following statements and mark True (T) or False (F) against each. (iii) 1 km = 100 cm False,
1 km = 1000 m
And
1 m = 100 cm
So
1 km = 1000 m = 1000 × 100
= 100000 cm

(Page 97) Which of the following is not a standard unit of measuring length? (i) millimetre (ii) centimetre (iii) kilometre (iv) handspanWe know that SI unit of length is metre ( m )
cm
mm
km
These are linked to metre
So can be called standard unit
Handspan
This is not a standard unit of measuring length

(Page 97) Search for the different scales or measuring tapes at your home and school. Find out the smallest value that can be measured using each of these scales. Record your observations in a tabular form.Measuring Tool
Smallest Value It Can Measure
15 cm scale (ruler)
30 cm scale (ruler)
Measuring tape (cloth)
Measuring Tape ( Steel )
1 mm
1 mm
1 mm
1 mm

(Page 97) Suppose the distance between your school and home is 1.5 km. Express it in metres.1 km = 1000 m
1.5 km = 1.5 × 1000 m = 15/10 ×1000
= 1500 m

(Page 98) Take a tumbler or a bottle. Measure the length of the curved part of the base of glass or bottle and record it.Take a thread. Wrap it carefully around the curved part of the base of bottle.
Make sure the thread fits exactly along the curved surface.
Mark the point on the thread where the loop completes.
Stretch the thread straight on a ruler.
Note the length. This is the curved length of the bottle base.

(Page 98) Measure the height of your friend and express it in (i) metres (ii) centimetres and (iii) millimetres.First we will do (ii) then (iii) and then (i)
(iii) 1 cm = 10 mm 170 cm = 10 × 170 mm = 1700 mm
(i) 1 m = 100 cm 100 cm = 1 m 1 cm = 1/100 m
170 cm = 1/100 × 170 m = 17/10 m = 1.7 m

(Page 98) You are given a coin. Estimate how many coins are required to be placed one after the other lengthwise, without leaving any gap between them, to cover the whole length of the chosen side of a notebook. Verify your estimate by measuring the same side of the notebook and the size of the coin using a 15-cm scale.Length of the notebook side = 29.4 cm
Diameter of one coin = 2.6 cm
Number of coins needed = 29.4 ÷ 2.6 = 11 coins (Approx.)
So, 11 coins are needed.

(Page 98) Give two examples each for linear, circular and oscillatory motion.Type of Motion Examples
Linear Motion Moving car on a straight road, A boy walking on a straight line
Circular Motion Blades of a fan, Hands of a clock
Oscillatory Motion Swinging pendulum, motion of a seesaw

(Page 98) Observe different objects around you. It is easier to express the lengths of some objects in mm, some in cm and some in m. Make a list of three objects in each category and enter them in the Table. Size Objects
mm
Thickness of a coin, Thickness of a note,
Thickness of a paper
cm
Length of a Pencil, Length of an eraser,
Length of a Pencil Box
m
Length of a Table, Length of a wall,
Length of a Cardboard

(Page 98) A rollercoaster track is made in the shape shown in Fig. A ball starts from point A and escapes through point F. Identify the types of motion of the ball on the rollercoaster and corresponding portions of the track.Portion of Track
A → B
B → C → D → E
E → F
Type of Motion
Linear motion
Circular motion
Linear motion

(Page 99) Tasneem wants to make a metre scale by herself. She considers the following materials for it—plywood, paper, cloth, stretchable rubber and steel. Which of these should she not use and why?Material Should She Use It ? Reason
Plywood Yes Hard and rigid, does not bend or stretch easily.
Paper No (Not ideal) O Can tear or get wrinkled; length can change if it absorbs moisture.
Cloth No Flexible and stretches, gives wrong readings.
Stretchable rubber No Changes length when stretched - not reliable for measuring.
Steel Yes Strong, durable, and accurate - commonly used in real metre scales.

(Page 99) Think, design and develop a card game on conversion of units of length to play with your friends. In this case, we will make 2 types of cards :-
Conversion Card - Here, we will ask different questions