GK
PHYSICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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TRUE
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FALSE
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Either A or B
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None of the above
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Detailed explanation-1: -For a projectile, the net force is the downward force of gravity; thus, the acceleration is downward. A downward acceleration could mean two things: the object is moving upward (has an upward velocity) and slowing down or the object is moving downward (has an downward velocity) and speeding up.
Detailed explanation-2: -TRUE-A projectile has a vertical acceleration of 9.8 m/s/s throughout the entire trajectory. This acceleration value is constant. This means that the vertical velocity changes by the same amount-9.8 m/s-during each second of its motion. There is a change in the vertical velocity by a constant amount.
Detailed explanation-3: -The only acceleration of a projectile is the downwards acceleration due to gravity (see Figure 1 below).
Detailed explanation-4: -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.