The takeoff is in essence an action that creates vertical speed.

踏跳动作的实质是创造垂直速度的过程。

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Jumping is grasping the chance to get the quickest vertical speed and reasonable jumping angel with powerful pressing and stretching.

跳段是把握蹬伸时机，以强有力的蹬伸获取尽量大的垂直速度和合理的腾起角度。

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The total loss ratio of horizontal speed was rather great. The jumpers could not get great vertical speed during the second and the third jump.

水平速度总损失率偏大，运动员在第二跳、第三跳起跳时没有获得较大的垂直速度，这直接影响了二、三跳的远度和比例。

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This number is calculated by considering both horizontal speed and vertical bounce of a tennis ball off a court.

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Finally, AgustaWestland surprised the HeliExpo crowd by revealing that it has been secretly testing an electrically powered tiltrotor, mixing the versatility of a vertical takeoff and land helicopter with the speed and range of a fixed-wing aircraft.

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Part of that need will be met in the future by a new generation of rotorcraft, including the revolutionary MV-22 tiltrotor that combines the vertical agility of a helicopter with the speed and range of a fixed-wing plane.

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