Endogenic and exogenic forces

Solar energy helps drive weather water cycle and external processes. Exam tip: write external energy source for exogenic forces.

Over long time internal construction and external denudation together change landforms. Exam tip: understand the term interaction.

An earthquake can bring major change in very short time. Exam tip: identify processes by their timescale.

An uplifted mountain is an endogenic result and river incision is an exogenic response. Exam tip: identify the relation between result and response.

Chemical weathering changes rock composition at the surface through external agents. Exam tip: use surface conditions as the basis.

Folded mountains form due to compression and tectonic movement. Exam tip: consider folding an endogenic tectonic process.

When energy decreases rivers wind or glaciers deposit material. Exam tip: link deposition with loss of energy.

Uplift can increase slope and energy causing renewed vertical cutting. Exam tip: understand the link between uplift and rejuvenation.

Solar energy drives the water cycle and running water is an exogenic agent. Exam tip: identify energy and agent separately.

The direct answer is B, downslope movement of material mainly under gravity. Mass movement means the collective movement of soil, rock, debris, or mud down a slope because gravity pulls it downward. Step by step: weathering may loosen material; the material lies on a slope; gravity acts on it; when the resisting force becomes insufficient, a mass moves downslope. Landslides, rockfalls, mudflows, and soil creep are examples, although their speeds differ. Option A is wrong because magma moving at depth is an internal volcanic or igneous movement, not mass movement of surface material down a slope. Option B is correct because it states the essential agent, gravity, and the direction, downslope. Option C, compression of the crust, is a tectonic force and may create folds or faults, but it is not the definition of mass movement. Option D, volcanic spreading of the seafloor, is a tectonic or volcanic process, not gravity-driven slope movement. Mass movement is usually grouped with exogenic processes because it acts on the surface and redistributes weathered material, even though gravity itself is a fundamental force. Exam cue: material plus slope plus gravity equals mass movement.

Present form is often the combined result of many processes. Exam tip: analyze both origin and modification.

Basin formation is endogenic subsidence and sediment filling is exogenic deposition. Exam tip: identify the two stages separately.

In physical weathering rock breaks but its chemical composition does not change. Exam tip: separate physical and chemical weathering.

An earthquake may destabilize a slope and gravity causes the landslide. Exam tip: write trigger and process separately.

A river deposits transported sediments to form a plain. Exam tip: remember the role of deposition in plain formation.

Continental uplift may be a slow but large-scale endogenic process. Exam tip: remember both sudden and slow endogenic actions.

Rock hardness affects the rate of exogenic erosion. Exam tip: understand structure and resistance.

Endogenic forces can create new relief and structures. Exam tip: link constructive role with landform formation.

In a landslide material moves downslope due to gravity. Exam tip: treat gravity as the main cause of mass movement.

Weathering weakens rock and makes erosion easier. Exam tip: understand weathering as preparation for erosion.

Exogenic forces act on or near Earth’s surface. Weathering breaks material down, erosion removes it from higher places, and deposition lays it down in lower or flatter places. When these processes continue over a long time, highlands are reduced and depressions receive sediment. The difference in height between high and low areas therefore becomes smaller, producing a general tendency toward leveling and reduced relief.

Option A is correct because it describes this combined effect of erosion and deposition. The process does not suddenly increase Earth’s internal heat, compress the crust in the way tectonic forces do, or produce magma. A river carrying sediment from a highland and depositing it in a low basin is a simple example. The result is gradual smoothing of the landscape, although local landforms may still develop during the process.

Direct answer: Option B, land cutting by gully erosion. Surface water is an exogenic agent because it works at the outside surface of Earth. During heavy or concentrated runoff, water cuts narrow channels called gullies and removes soil and loose rock. Option B is correct because it directly shows moving surface water shaping the land. Option A, formation of a fault line, results mainly from internal tectonic stress and crustal movement, so it is endogenic. Option C, formation of a magma chamber, occurs below the surface through internal magmatic processes, not through surface water. Option D, compression of the crust, is also an internal tectonic process. Thus the reasoning is: identify the agent, check where it acts, and identify the landform process. Flowing water at the surface means an exogenic example. Memory cue: rain and rivers usually point to exogenic work.

Endogenic uplift can strengthen conditions for exogenic erosion. Exam tip: identify the chain of causes.

On desert surfaces weathering and erosion can cut slopes to form pediments. Exam tip: identify external forces in desert landforms.

Energy source and place of action clarify the correct category of a process. Exam tip: write logic along with examples.