GROWTH DEVELOPMENT CHILD
SUMMATIVE ASSESSMENT
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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A 5 N force is applied to a 3 kg ball to change its velocity from +9 m/s to +3 m/s. The impulse on the ball is ____ N s.
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-2.5
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-10
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-18
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-45
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none of these
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Explanation:
Detailed explanation-1: -The impulse on the ball will be “18 kg.
Detailed explanation-2: -Upon rebounding, the object has a momentum of-15 units (kg•m/s). The-15 is the product of mass (3 kg) and velocity (-5 m/s). The “-” sign is used since the object is now moving in the opposite direction as the original motion.
Detailed explanation-3: -Fgrav = m • g = (5 kg) • (9.8 m/s/s) = 49 N.
Detailed explanation-4: -The change in velocity is 4 m/s. Given F = 12 N, m = 3 kg and t = 1 s. Thus, the change in velocity is 4 m/s.
There is 1 question to complete.