Explanation: The longitudinal difference between two places on Earth is the angular distance between their longitudes. In the context of India, the longitudinal span from Gujarat to Arunachal Pradesh is a significant geographical feature that helps in understanding the country's east-west extent.
Gujarat is located in the western part of India, with its westernmost point near the Arabian Sea. Arunachal Pradesh, on the other hand, is situated in the northeastern part of India, bordering China and Myanmar. The longitudinal difference between these two states is a measure of the angular distance between their respective longitudes.
To understand this concept, it is important to know that the Earth is divided into 360 degrees of longitude, with the Prime Meridian (0$^\circ$ longitude) passing through Greenwich, England. Longitudes are measured in degrees east or west from the Prime Meridian, up to 180$^\circ$ in either direction.
In the case of Gujarat and Arunachal Pradesh, the westernmost part of Gujarat is approximately at 68$^\circ$E longitude, while the easternmost part of Arunachal Pradesh is around 98$^\circ$E longitude. The difference between these two longitudes is 30$^\circ$.
This longitudinal difference is significant because it affects various aspects of life in these regions, such as time zones, climate, and daylight hours. For example, the time difference between Gujarat and Arunachal Pradesh is approximately 1 hour and 30 minutes, which is a direct result of their longitudinal span.
Understanding the longitudinal difference between different parts of India is crucial for students of geography and those preparing for competitive examinations that test knowledge of Indian geography. It helps in comprehending the geographical layout of the country and the implications of its east-west span on various socio-economic and environmental factors.
In conclusion, the longitudinal difference between Gujarat and Arunachal Pradesh is 30$^\circ$, reflecting the significant east-west span of India and the geographical diversity within the country.