NCERT Solutions For Class 6 Science Chapter – 10
Q1. Give two examples each of modes of transport used on land , water and air.
Answer:-
Two examples of modes of transport used on land are buses and wheel carts.
Two examples of modes of transport used on water are ships and boats.
Two example of modes of transport used in air are aeroplanes and helicopter.
Q2. Fill in the blanks:
- One meter is __________ cm.
- Five kilometers is ____________ m.
- Motion of a child on a swing is _______.
- Motion of the needle of a sewing machine is _________.
- Motion of wheel of a bicycle is ________.
Answer:-
- 100
- 5000
- Periodic
- Periodic
- Circular
Q3. Why can a pace or a footstep not be used as a standard unit of length?
Answer:-
The size of the foot varies from person to person. If footsteps of two persons are used to measure the length respectively. Then the two distances may not be equal. Thus, a footstep is not a constant quantity. Hence , it cannot be used as a standard unit of length.
Q4. Arrange the following lengths in their increasing magnitude:
1 meter . 1 centimeter , 1 kilometer , 1 millimeter
Answer:-
1 millimeter < 1 centimeter < 1 meter < 1 kilometer
Q5. The height of a person is 1.65 m Express it into cm and mm.
Answer:-
Height of the person = 1.65 m
1 m = 100 cm
1.65 m = 1.65 x 100 cm = 165 cm
Hence , the height of the person is 165 cm.
Again, 1 m = 100 cm = 1000 mm
Therefore, 1.65 m = 1.65 x 1000 mm = 1650 mm.
Q6. The distance between Radha home and her school is 3250 m. Express the distance into km.
Answer:-
The distance between Radha home and her school is 3250 m.
1 km = 1000 m
1000 m = 1 km
3250 m = 1/1000 x 3250 = 3.25 km
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?
Answer:-
The reading of the scale at one end is 3.0 cm and at the other end is 33.1 cm.
Therefore, the length of the knitting needle I given by subtracting both the readings (33.1 – 3.0) = 30.1 cm.
Q8. Write the similarities and the difference between the motion of a bicycle and a ceiling fan that has been switched on.
Answer:-
Similarities between the motion of a bicycle and a ceiling fan:
- The blades of a fan and the wheels of a bicycle are fixed at a point.
- Both have circulars motion about their respective fixed points.
Differences between the motion of a bicycle and a ceiling fan:
- A bicycle has linear motion, whereas the blades of a ceiling fan do not have linear motion.
- The motion of the blades of a fan is periodic whereas the motion of a bicycle is rectilinear motion.
Q9. Why would you not like to use a measuring tape made of an elastic material like rubber to measure distance? What would be some of the problems you would meet in telling someone about a distance you measured with such a tape ?
Answer:-
An elastic measuring tape is stretchable. It cannot be used to measure distance because the length of the tape may change on stretching. As a result, the measured length would not be correct.
If you measure the length of an object twice using an elastic tape, then you may get different values of the same length each time. This is because elastic tapes are stretchable.
Q10. Give two examples of periodic motion.
Answer:-
Examples of periodic motion:
- Motion of a pendulum
The bob of a pendulum repeats itself at a certain time period. This motion is called periodic motion.
- Motion of a boy sitting on a swing
The motion of a swing repeats itself at a certain time period. Hence ,a boy sitting on a swing has periodic motion.