Chapter 28, Problem 8TE

To determine

The role of frictional drag in the external movement of a glacier and its effect on the internal movement.

Answer to Problem 8TE

The role of frictional drag in the external movement is that glaciers' movement is fastest at the surface and slowest at the bottom. If also affects the internal movement of a glacier by causing deformation in ice.

Explanation of Solution

The movement of a glacier is both external and internal movement, which is caused due to frictional drag. The external drive of a glacier is slow at the bottom surface. On the other hand, the movement is fast on the top surface, as compared to the middle and bottom. The ice at the sides and base will move at a slower pace with respect to the ice at the glacier's surface. Frictional drag also affects the internal movement of a glacier, causing the deformation in the glacier itself. The ice mass moves due to this deformation within glacier ice, which helps in lubrication also.

Conclusion:

Therefore, the role of frictional drag in the external movement is that glaciers' movement is fastest at the surface and slowest at the bottom. If also affects the internal movement of a glacier by causing deformation in ice.