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1.当一艘轮船从旧金山返航上海时,海员们在甲板上调到的从正午到正午的时间间隔,应是:A.恒星日;B.太阳日;C.比恒星日稍短些;D.比太阳日稍长些? 此题可借助于“恒星日与太阳日”图来进行剖析。假设轮船停在P点的位置不移动时,则船上测到的由正午到正午的时间间隔将是由P再到P的周期,即一个太阳日。根据题意,轮船的位置在由东向西移动,即逆地球自转方向航行。假设该轮船由P点航行到P’时,当太阳第二次直射P点所在的经线时,而船上实测到的太阳却尚未正午。等到太阳直射P’所在的经线时,船上才测
1. When a ship returns from San Francisco to Shanghai, the time interval from noon to noon to which the seafarers are deployed on the deck should be: A. Stellar day; B. Sun day; C. Shorter than the star day; D Is it slightly longer than the sun day? This question can be analyzed by means of the “star day and sun day” map. Assume that the ship stops at the point P. The time interval from noon to noon measured on the ship will be the period from P to P, ie, a solar day. According to the question, the position of the ship is moving from east to west, that is, in the direction of the rotation of the earth. Suppose the ship sails from point P to P’. When the sun shines directly on the meridian of point P for the second time, the sun measured on the ship is not yet noon. When the sun is directly in the warp of P’, it is measured on the ship.