41.
a.In a thunderstorm, lightning is seen before thunder is heard.
b. The frequency of light waves is higher than that of sound waves.
42.
a.Momentum is not conserved in an inelastic collision.
b.Kinetic energy is lost in an inelastic collision.
判別以上各題的2句句子~~~
如果2句都正確,就要判別第2係咪第1既正確解釋~~
Physics MC Question
2007-04-06 4:05 am
回答 (2)
2007-04-06 4:51 am
✔ 最佳答案
41) 答案是B 光速是大於聲速，所以會先看見閃電才聽到雷聲。(正確)
光的頻率為4x1014Hz ~ 7.5x1014Hz，而聲波的頻率為20Hz~20000Hz，所以光的頻率大於聲，但和它第一句波的速度無關。所以問案是 B。
42) 答案是D
無論彈性或非彈性碰撞，只要沒有外力的情況下，動量都是守恒的。所以第一句是錯。
非彈性碰撞時會損失動能。所以第二句是正確。
2007-04-06 4:41 am
41. True False (The speed of light waves is faster than that of sound waves.)
42. I'm not sure
42. I'm not sure
參考: me
收錄日期: 2021-04-22 00:29:51
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