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Space Passed Over

المؤلف:  GEORGE A. HOADLEY

المصدر:  ESSENTIALS OF PHYSICS

الجزء والصفحة:  p-36

2025-10-21

977

 The space passed over by a moving body depends upon two elements, speed and time.

A train moving with an average speed of 20 mi. per hour moves 60 mi. in 3 hr. This relation may be expressed by the equation 60 = 20 × 3

Space passed over = Average speed Time, or, writing S for space passed over, v for average speed, and t for time, we have the formula S = vt.

NOTE. - The student should observe that "Space passed over = Average speed × Time" is not to be understood literally. It is merely a short and convenient way of saying, "The number of units of length passed over = the number of units of length in the average speed per unit of time× the number of units of time". The briefer wording of such, formulas as this is so convenient and so commonly employed in actual use, that it will be used in this book; but the student should always bear in mind that every element, or letter, in a formula represents merely a number.