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  • Smart Learning for All

  • Topic: Balanced and Unbalanced Forces.

  • How are we able to stand on the earth without falling into the center of the earth?

  • That was a nice balancing act.

  • 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.

  • Then the forces are said to be balanced.

  • 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?

  • Were they balanced or unbalanced?

  • In this case, unbalanced forces were acting on him.

  • On earth, many forces act on an object.

  • One of them is gravitational force of the earth.

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

  • Towards the center of the earth.

  • Let's get back to the question.

  • 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.

  • Did you see that?

  • He landed safely.

  • 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.

  • This force is called the normal force.

  • It is equal to the gravitational force.

  • 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.

  • Net force is zero.

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

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A2 US

為什麼我們不掉進地球中心?| 我的天啊!我的天啊!我的天啊!我的天啊!我的天啊!我的天啊 (Why dont we fall into the center of the earth? | #aumsum)

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    AumSum posted on 2021/01/14
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