geomorphology & earth landforms section 1 MCQ Questions & Answers Detailed Explanation

Answer: (c)

Answer: (d)

Answer: (c)

A mushroom rock also called a rock pedestal or a pedestal rock is a naturally occurring rock whose shape, as its name implies, strikingly resembles a mushroom.

Usually found in desert areas, these rocks are formed over thousands of years when wind erosion of an isolated rocky outcrop progresses at a different rate at its bottom to that at its top.

Answer: (a)

The youthful stage of the river is when water flow is the quickest. Because of a steep slope and steep channel gradient in this stage, rivers actively deepen their valleys through vertical erosion.

The valley becomes deep and narrow characterized by steep valley side slopes of the convex plan. Waterfalls, V-shaped valleys and interlocking spurs are features of this stage.

Answer: (d)

Answer: (b)

A traveller crossing the International Date Line eastbound subtracts one day, or 24 hours so that the calendar date to the west of the line is repeated. Crossing the IDL westbound results in 24 hours being added, advancing the calendar date by one day.

The International Date Line is necessary to have a fixed, albeit arbitrary, boundary on the globe where the calendar date advances in the westbound direction.