GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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slow down, stop, and speed up
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speed up, stop, and slow down
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slow down, stop, and slow down
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speed up, stop, and speed up
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Detailed explanation-1: -As a projectile rises towards the peak of its trajectory, the vertical velocity will decrease; as it falls from the peak of its trajectory, its vertical velocity will decrease.
Detailed explanation-2: -The horizontal velocity of a projectile is constant (a never changing in value), There is a vertical acceleration caused by gravity; its value is 9.8 m/s/s, down, The vertical velocity of a projectile changes by 9.8 m/s each second, The horizontal motion of a projectile is independent of its vertical motion.
Detailed explanation-3: -As a projectile rises towards the peak of its trajectory, the (MAGNITUDE OF) vertical velocity will decrease; as it falls from the peak of its trajectory, its (MAGNITUDE OF) vertical velocity will decrease.
Detailed explanation-4: -Therefore, the acceleration of a projectile fired vertically upwards is g=−9.81m/s2 g = − 9.81 m / s 2 . This is negative because its direction is downward towards the center of the earth.