3 17. a) Which type of watch is used to measure time intervals in a 100 metre race? b) What are the standard units of length and mass? c) Why is a foot step, or a hand span, not used as a standard unit of length? namasta
Answers
Answer:
a) In order to measure the time in an athletics meet, stopwatches are used. It conveys the total time taken by the athletes to complete the race.
b)In SI units, the standard for mass is the kilogram and the standard for length is the meter the standard for volume is the cubic decimeter.
c)The size of the foot and hand varies from person to person. If footsteps or hand span of two persons are used to measure the length respectively, then the two distances may not be equal. Thus, a footstep or hand span are not the constant quantities. Hence, they cannot be used as a standard unit of length
hope you can understand now
Answer:
1.stop watch
2.length:meter. mass kilogram
c. A pace or a footstep cannot be used as a standard unit of length because the length of footstep, forearm length and hand span of different person is different. ... So footsteps and other such measuring systems cannot be use as standard unit.