The latest trends in geography include:
1. Geospatial technology: The use of Geographic Information Systems (GIS) and Remote Sensing (RS) for mapping, environmental monitoring, and urban planning.
2. Sustainability and climate change: The growing importance of studying climate change, sustainability, and environmental impact in geographical studies.
3. Urbanization: An increasing focus on the study of urban geography, including issues of urbanization, migration, and the impact of cities on the environment.
4. Human geography: The study of the relationship between people and their environments, focusing on cultural, economic, and political geography.
5. Globalization: Analyzing the effects of globalization on local cultures, economies, and environments. These trends reflect the dynamic nature of geography as a discipline, incorporating technological advances and global concerns.
Explain the construction of a spherical wavefront by using Huygens' principle.
The perpendicular distance of the plane \( r \cdot (3\hat{i} + 4\hat{j} + 12\hat{k}) = 78 \) from the origin is __________.
Derive an expression for maximum speed of a vehicle moving along a horizontal circular track.