Quiz Questions 13 February 2023 (Key)

Q1.Consider the following statements:

1. Standard Meridian of India passing through Mirzapur is taken as the standard time for the whole country

2. The latitudinal extent influences the duration of the day and night, as one moves from south to north

Select the correct answer using the code given below:

A. 1 only
B. 2 only
C. Both 1 and 2
D. Neither 1 nor 2

Explanation:

From Gujarat to Arunachal Pradesh there is a time lag of two hours. Hence, time along the Standard Meridian of India (82°30’E) passing through Mirzapur (in Uttar Pradesh) is taken as the standard time for the whole country. The latitudinal extent influences the duration of the day and night, as one moves from south to north.

Q2. Consider the following statements

1. The earth rotates from west to east, so every 15° we go westwards, local time is advanced by1 hour.
2. If we go eastwards, local time is retarded by 1 hour.
3. We may thus conclude that places west of Greenwich see the sun later and lose time whereas placeseast of Greenwich see the sun earlier and gain time.

Select the correct answer using the code given below :

A. 1 only
B. 1 and
C. 2 and 3
D. 3 only

Explanation:

The earth rotates from west to east, so every 15° we go eastwards, local time is advanced by 1 hour.
Hence, statement 1 is not correct.
Conversely, if we go westwards, local time is retarded by 1 hour.
Hence, statement 2 is not correct.
Also, it can be concluded that places east of Greenwich see the sun earlier and gain time, whereas places west of Greenwich see the sun later and lose time.
Hence, statement 3 is correct.

Q3.Consider the following statements:

1.The effect of Daylight Saving Time on daily life varies according to how far east or west the
location is within a time zone.

2.When DST begins, clocks skip one hour.

3. DST begins in autumn season.

Which of the statements given above is/are correct?

A. 1, 2 and 3
B. 1 and 2 only
C. 2 only
D. 3 only

Explanation:

A time zone represents a geographic area. All the clocks in a given time zone have the same time being shown. That same time is often called as STANDARD TIME.
Many countries like USA & Russia have more than one time zone because these countries are so much big in terms of the width that having one common time zone will not work for them.
Daylight Saving is a procedure in which the time in the clock is adjusted forward in spring & is readjusted backward in autumn
Locations farther east inside the time zone benefit more from DST than locations farther west in the same time zone.

Q4. Why sometimes a ‘leap second’ is added to atomic clocks?

1. To account for the additional time at the beginning of a leap year

2. To compensate for slowdown in the Earth’s rotation

Which of the above is/are correct?

A. 1 only
B. 2 only
C. Both 1 and 2
D. None

Explanation:

An atomic clock at National Physical Laboratory (NPL) in New Delhi added ‘leap second’ (extra one second) to the Indian Standard Time (IST) on 1 January 2017 to synchronise with the Earth’s rotational clock.
The clock was programmed to add an extra second to the year 2017 in order to compensate for a slowdown in the Earth’s rotation.
•The Earth and rotation around its own axis is not regular, as sometimes slows down and sometimes speeds up due to various factors, including moon’s gravitational forces and earthquakes
•As a result, astronomical time (UT1) gradually falls out of sync with atomic time (UTC)
When the difference between UTC and UT1 approaches 0.9 seconds, a leap second is added to UTC through atomic clocks worldwide to match both times.
•This one second shift is critical for applications requiring time accuracies in the nanosecond scale, which are critical in the fields of astronomy, satellite navigation, communication networks etc.

Q5. With reference to the Atomic clock, consider the following statements.

1. It is the most accurate time measurement device.

2.It is used in the navigation satellite systems.

Which of the statements given above is/are correct?

A. 1 only
B. 2 only
C. Both 1 and 2
D. None

Explanation:

Statement 1 is correct.
An Atomic clock is the most accurate type of clock which is regulated by the vibrations of an atomic or molecular system such as caesium or ammonia.
The principle of operation of an atomic clock is based on atomic physics; it uses the microwave signal that electrons in atoms emit when they change energy levels.
Atomic physics is the field of physics that studies atoms as an isolated system of electrons and an atomic nucleus.
It is primarily concerned with the arrangement of electrons around the nucleus and the processes by which these arrangements change.

Statement 2 is correct.
They provide accurate time and frequency standards and are used as primary standards for international time distribution services, to control the wave frequency of television broadcasts, and in global navigation satellite systems such as GPS.

Recently three atomic clocks onboard a single satellite of the NAVIC Indian regional navigation satellite system have failed and efforts are being taken to rectify/replace the clocks.

Q6. Consider the following statements

1.A solar day is nearly 4 minutes smaller than a sidereal day

2.Approximately 1° is the distance covered by earth in its orbit everyday

3.The mean solar day at present is 86400 seconds

Which among the above statements is / are correct?

A. 1 and 2 only
B. 1 and 3 only
C. 2 only
D. 2 and 3 only

Explanation:

A solar day is nearly 4 minutes longer than a sidereal day. The mean solar day at present is 86400.002 seconds, It was 86400 in 1820

Q7. An Isochrone is defined as a line drawn on a map connecting points of :

A. Equal salinity
B. Equal time difference
C. Equal rainfall
D. Same magnetic dip

Explanation:

An Isochrone is defined as “a line drawn on a map connecting points at which something occurs or arrives at the same time”.

Q8. When it is 6 PM, Sunday at Greenwich, what is the time and day at a place 105 degree East?

A. 1 AM, Monday
B. 11 AM, Sunday
C. 11 AM, Monday
D. 1 PM, Sunday

Q9. With respect to the Indian Standard Time (IST- 82°30’), consider the following statements:

1. The IST meridian intersects the Tropic of Cancer in the state of Chhattisgarh.
2. The IST is shared by the neighbouring Sri Lanka.
3. 3.Chaibagaan refers to India’s official Daylight Saving Time (DST) used in north-eastern states.

Which of the statements given above is/are correct?

A. 1 and 2 only
B. 1 and 3 Only
C. 2 and 3 only
D. 1, 2 and 3

Explanation:

Statement 1 is correct.
Established on September 1, 1947, IST corresponds to the time schedule along the 82.5°E longitude near Mirzapur in Uttar Pradesh.
States located to the west of this longitude have more daylight hours compared to those in the east.
Indian Standard Time is five and a half hours ahead of UTC / GMT. Tropic of cancer and IST meridian intersect at Koriya district in Chhattisgarh
Statement 2 is correct.
The Sri Lanka Time reverted on 15 April 2006 to match Indian Standard Time calculated from the Allahabad Observatory in India 82.5 ° longitude East of Greenwich, the reference point for GMT
Statement 3 is not correct.
India has no official Daylight Saving Time (DST) although the country spans more than 2000 Km East to West.
Some of the North eastern states have a different ‘Tea Garden Time’ to save Daylight. Chaibagaan or bagaan time was set one hour ahead of IST for tea estates, collieries and oil industry of Assam. Most tea estates still follow this time, so does the 112-year-old Digboi Refinery in eastern Assam.