The blog discusses the Questions and Answers from the lesson 2, History and the Concept of Time, Environmental Science, Part 2, from Class 5. Students can use these answers for reference in their studies.
Q1. Fill in the blanks.
1. The calendar that we use today is based on the . . . . . . . . . . . . . . ..
2. The period before Common Era or Christian Era is known as the . . .
1. The calendar that we use today is based on the Common Era/ Christian Era.
2. The period before Common Era or Christian Era is known as the Before Christ (BC).
Q2. Answer each question in one sentence.
1. Which scientific methods are used to estimate the age of the layers of soil and the remains found in them ?
Ans. The scientific methods used to estimate the age of the layers of soil and the remains found in them are :
(a) Carbon-14 analysis
(b) Tree-rings analysis (Dendrochronology)
2. How is the first century of the Common Era written ?
Ans. The first century of the Common Era written as, 1-100 CE or 1-100 AD.
Q3. Answer the following questions in brief.
1. What is meant by unilinear division of time ?
Ans. The unilinear division of time is as follows :
(a) Seven days make a week, two weeks make a fortnight, four weeks make a month.
(b) Twelve months make a year, hundred years make a century and ten centuries make a millennium.
2. What are the units of measuring time ?
Ans. To measure time is to measure the length of time. We know the following units of measuring time :
(a) second, minute, hour, day, week, fortnight, month, year, century and millennium.
(b) the second is the smallest unit of measuring time.
Q4. Complete the chart given below :