Name: 為什麼我們不會掉進地心？ | #aumsum (Why dont we fall into the center of the earth? | #aumsum)
Uploaded: 2025-12-08T10:50:56.000Z
Duration: 4 min 8 s
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How are we able to stand on the earth without falling into the center of the earth?

Do you know there are certain forces around us which keep us balanced or unbalanced?

Force is a push or a pull exerted on an object.

Every object on the earth experiences various forces.

When a number of forces acting on an object are such that their resultant force is zero.

Whereas, when a number of forces acting on an object are such that their resultant force is not equal to zero.

Then the forces are said to be unbalanced.

When he was falling which forces were acting on him?

In this case, unbalanced forces were acting on him.

One of them is gravitational force of the earth.

Gravitational force of the earth is the force which pulls all the objects downwards.

When he was falling, the gravitational force over powered all other forces.

So, the resultant force was not equal to zero.

Hence, we can conclude that unbalanced forces were acting on him.

But if the gravitational force was pulling him towards the center of the earth.

Why did he fall on the ground and not into the center of the earth?

We know that gravitational force is pulling us downwards.

However, there is another force exerted by the ground which pushes us upwards.

Normal force is exerted by a surface only when we are in contact with it.

Since these two forces acting on us are equal but opposite to each other, their resultant.

Thus, these balanced forces keep us from falling into the center of the earth.

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