Test: The Changing Face of Earth - Class 7 MCQ

Endogenic forces come from within the Earth and cause changes like earthquakes and volcanic eruptions. External forces, on the other hand, come from outside the Earth like rain and wind, and also help in shaping the Earth's surface.

• Continents are formed by the movement of tectonic plates deep below the Earth's surface. These plates are like giant puzzle pieces that are always shifting and moving.
• When they collide or separate, they can create new land or change the shape of existing continents.
• So, continents are not just fixed landmasses but are always changing because of these movements.

Endogenic forces come from deep within the Earth and cause changes on the surface like creating mountains, valleys, and volcanoes. These forces are very strong and shape the land around us.

• Fold mountains are created when two plates collide, pushing against each other. This pressure causes the land in between them to be pushed upwards, forming massive folds in the Earth's crust. Imagine if you have two big books on a table and you push them towards each other, the pages in the middle would start to rise up just like how fold mountains are formed.

Fold Mountains are created when two plates push towards each other, causing the land between them to be uplifted in massive folds like the Himalayas, the Alps, and the Rockies. The plates come together, pushing the land upwards.

• A seismograph is a special machine that helps scientists measure how strong an earthquake is. It draws wavy lines on paper to show how much the ground is shaking.
• Just like how a heart monitor helps doctors see how healthy a heart is, a seismograph helps scientists understand how powerful an earthquake is!

Earthquakes usually happen along plate boundaries where tectonic plates meet and interact. These are places where the Earth's plates move against each other, causing shaking and tremors that we feel on the surface. It's like when two big puzzle pieces rub together and create a big shake!

• A volcano is like a special hole in the Earth's crust where hot melted rock called magma comes out.
• When this magma comes out, sometimes it can explode and throw out ash and rocks.
• This can build up over time to make big mountains.
• So, a volcano is an opening in the Earth where hot stuff can burst out.

A volcano is a vent or an opening in the Earth's crust through which magma, ash, and smoke erupt. When this eruption happens, it can cause lots of damage. The hot liquid that flows out of a volcano is called lava. If the lava cools down, it can form big mountains over time.

• Objective: Exogenic forces are like nature's sculptors that work to flatten the Earth's surface. They help in making sure the land is not too bumpy or too rough, creating a more even and smooth surface for us to live on. It's like nature's way of giving us a nice, flat playground to play on and build our homes.

Rivers slow down as they move from mountains to plains. This is because the land becomes flatter, so the water doesn't have to rush as fast. When rivers slow down, they can create big bends called meanders, which are like loops in the river's path.

Glaciers shape landscapes by moving slowly and carving valleys over time. When the ice melts, it fills the hollows with water, creating glacial lakes. Imagine a giant ice bulldozer slowly carving and shaping the land as it moves, leaving behind valleys and lakes.

The glaciers shape valleys by the weight of their ice. The heavy ice carves out U-shaped valleys over time.

• The Earth's surface changes because of two types of forces: endogenic forces and exogenic forces.
• Endogenic forces come from deep within the Earth, like when the ground moves during earthquakes or when volcanoes erupt.
• Exogenic forces, on the other hand, work on the Earth's surface, like when rivers shape the land or when wind erodes rocks.
• These forces together shape our world, making mountains, valleys, and all the landforms we see around us.

• Tectonic plates move because of heat energy from deep inside the Earth. This heat creates currents that push the plates, making them move. It's like when you push a toy car and it starts moving on its own. So, the heat from inside the Earth is like the hand that pushes the plates around. This movement is what causes earthquakes and builds mountains. Cool, right?

Tectonic plates move due to heat energy from deep inside the Earth. Heat from the outer core creates convection currents in the lower mantle, which push the plates, causing different types of movements.

• Fold Mountains are formed when two plates push towards each other, causing the land between them to be uplifted in massive folds like a crumpled piece of paper. This process creates majestic mountain ranges like the Himalayas, the Alps, and the Rockies. Imagine pushing two hands together to make a big fold; that's how Fold Mountains are created!

• A volcano is like a big hole in the ground where hot stuff like lava comes out.
• It's not just any mountain, it's special because it has this opening where things from deep inside the Earth can burst out.
• So, when you think of a volcano, imagine a big crack in the Earth's skin where fire and rocks can explode out.

A volcano is like a mountain with a hole on top. Sometimes, hot melted rock called magma comes out of this hole along with ash and smoke. This can happen when the volcano erupts.

• Weathering is like when rocks slowly break down and crumble into tiny pieces because of things like rain, heat, or even plants and animals touching them.
• It's like how a big rock can become small grains of sand over many, many years.
• So, weathering is when rocks change because of nature's gentle touch.

Rivers form meanders, which are large bends and loops, as they flow through plains. Imagine a river taking a twisty path like a snake! This happens because the water in the river keeps moving and shaping the land around it, creating these beautiful bends.

Wind plays a big role in shaping deserts by moving sand and rocks from one place to another. This movement helps in making sand dunes and carving rocks over a long time. So, wind is like a sculptor that slowly changes the face of the desert by moving sand and rocks around.

Wind helps to shape deserts through erosion, which means wearing away rocks and soil. This happens when the wind carries sand and particles that scrape and break down the land over time.

Wind is like a powerful artist in deserts. It moves the sand and rocks around, creating shapes and patterns in the land. This is called erosion and deposition. So, the statement is True!