Question

Question 1

We did not have accurate scientific estimates of the age of the Earth until the 1960's and 1970's because:

a. Reliable radiometric techniques that could date the earliest time periods were not available until then.

b. The major religions around the world stopped scientists from finding out the real date.

c. No one wanted to know this fact before the 1960's and 1970's.

Question 2

Which of the following is a relative date?

a. The first hominid dates to around 6 million years ago.

b. Fossil A is 1000 years older than fossil B.

c. Fossil B is older than fossil C.

Question 3

The statistical measure of the rate of decay of a radioactive isotope is termed its half-life.

True or False

Answer 1

Q-1. The answer will be option "a" - Reliable radiometric techniques that could date the earliest time periods were not available until then.

The radiometric technique is a method that is used to date rocks and other natural or artificial objects based on the known decay rate of radioactive isotopes. The early radioactive techniques are first discovered in the early 20th century.

Radiocarbon dating was developed in the late 1940s at the University of Chicago by Willard Libby. But effective and reliable techniques came in the late 1960s.

On progressive Science and Tech in the 20th century, it is not justiciable to say The major religions around the world stopped scientists from finding out the real date. So option b is incorrect

There is always a need for this technology. So option c is incorrect.

Q- 2. First, we have to know about what Relative Date means. It is a period of time that is relative to the current date.

The first option "a " " The first hominid dates to around 6 million years ago " expressed relative to the current date. So it correct.

But options b and c relate to other fossils for comparison that is not relative to the current date. so these options are false.

Q-3.  Half-life is the time required for a quantity to reduce to half of its initial value. The rate of radioactive decay means the rate of a radioactive substance to emit particles. Activity is usually measure in disintegrations per second. But half life is a different thing. It measures the time it takes for a given amount of the substance to become reduced by half as a consequence of decay, and therefore, the emission of radiation. So this statement is False.