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This is the "textbook" case of the vertical motion of an object falling a small distance close to the surface of a planet. It is a good approximation in air as long as the force of gravity on the object is much greater than the force of air resistance, or equivalently the object's velocity is always much less than the terminal velocity (see below)

INTO JAPANESE

これは、惑星の表面に少し近づいた物体の垂直運動の「教科書」の場合です。物体にかかる重力が空気抵抗の力よりもはるかに大きいか、同等に物体の速度が常に終端速度よりもはるかに小さい限り、これは空気中での適切な近似です（以下を参照）。

BACK INTO ENGLISH

This is the case for a "textbook" of vertical motion of an object that is a little closer to the surface of the planet. This is a good approximation in air, as long as the gravity on the object is much greater than the force of air resistance, or equally the velocity of the object is always much less than the terminal velocity (see below).

INTO JAPANESE

これは、惑星の表面に少し近い物体の垂直運動の「教科書」の場合です。これは、オブジェクトの重力が空気抵抗の力よりもはるかに大きいか、オブジェクトの速度が常に終端速度よりもはるかに小さい限り、空気中での適切な近似です（以下を参照）。

BACK INTO ENGLISH

This is the case for a "textbook" of vertical motion of an object a little closer to the surface of the planet. This is a good approximation in air, as long as the object's gravity is much greater than the force of air resistance, or the object's velocity is always much less than the terminal velocity (see below).

INTO JAPANESE

これは、惑星の表面に少し近い物体の垂直運動の「教科書」の場合です。これは、オブジェクトの重力が空気抵抗の力よりもはるかに大きいか、オブジェクトの速度が常に終端速度よりもはるかに小さい限り、空気中での適切な近似値です（以下を参照）。

BACK INTO ENGLISH

This is the case for a "textbook" of vertical motion of an object a little closer to the surface of the planet. This is a good approximation in air, as long as the object's gravity is much greater than the force of air resistance, or the object's velocity is always much less than the terminal velocity (see below).