10. MOTION AND MEASUREMENT OF DISTANCES Science class 6 in English Medium ncert book solutions Exercise (NCERT Text Book)

Text book Exercise: 

Q1: Give two examples each, of modes of transport used on land, water and air.

Ans: Two examples of each.

Land transport: bus and train.

Water transport: boat and   ship.

Air transport: Helicopter and aeroplane. 

Q2: Fill in the blanks:
(i) One metre is ______________ cm.
(ii) Five kilometre is ______________ m.
(iii)Motion of a child on a swing is ______________.
(iv) Motion of the needle of a sewing machine is ______________.
(v) Motion of wheel of a bicycle is______________.

Ans: 

(i) 100

(ii)  500

(iii) periodic motion

(iv) periodic motion

(v)  rotational motion

Q3:  Why can a pace or a footstep not be used as a standard unit of length?

Ans: Standarrd unit of length must have a fixed numeric value while footstep does have so. 

Q4: Arrange the following lengths in their increasing magnitude:
1 metre, 1 centimetre, 1 kilometre,1 millimetre.

Ans: 1 milimetre, 1 centimetre, 1 metre, 1 kilometre

Q5: The height of a person is 1.65 m. Express it into cm and mm.

Ans: 

The height of a person = 1.65 m 

         In centimetre, 

           1 metre = 100 cm 

           1.65 m = 1.65 x 100 cm 

                           = 165 cm 

          In milimetre, 

           1 centimetre = 10 milimetre

           1 metre = 100 centimetre

           Or        = 100 x 10 milimetre 

                      = 1000 milimetre

            1.65 metre = 1.65 x 1000 milimetre

                            = 1650 milimetre          

Q6: The distance between Radha's home and her school is 3250 m. Express this distance into km.

Ans:

Q7: While measuring the length of a knitting needle, the reading of the scale at one end is 3.0 cm and at the other end is 33.1 cm. What is the length of the needle?

Ans:

Reading of scale at one end = 3.0 cm

Reading of scale at other end = 33.1 cm

Distance between two end = 33.1 - 3.0 cm

                                           = 30.1 cm

Q8: Write the similarities and differences between the motion of a bicycle and a ceiling fan that has been switched on.

Ans: Similarities: the motion of a bicycle and a celing fan both have circular motion. Differences: The bicycle moves on straight line but ceiling fan does not move so. 

Q9: Why could you not use an elastic measuring tape to measure distance? What would be some of the problems you would meet in telling someone about a distance you measured with an elastic tape?

Ans:

Q10: Give two examples of periodic motion.

Ans:

(i) The motion of child on a swing.

(ii) moving here and there the branches of tree.