试题与答案

在距地面30m高处,以10m/s的速度抛出一质量为1kg的物体(g取10m/s2

题型:问答题

题目:

在距地面30m高处,以10m/s的速度抛出一质量为1kg的物体(g取10m/s2).求

(1)抛出时人对物体做功为多少?

(2)自抛出到落地,重力对物体做功为多少?

(3)落地时物体的动能是多少?

答案:

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Blues musician Paul "Poboy" Smith, born in Tupelo, Mississippi, in 1936, has since 1958 been a fixture on the southern blues scene after the release of his debut album in that year.()

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B. Being born in 1936 in Tupelo, Mississippi, blues musician Paul "Poboy" Smith released his debut album in 1958 and has been a fixture on the southern blues scene since then.

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