Centuries: 15th century - 16th century - 17th century
Decades: 1490s 1500s 1510s 1520s 1530s - 1540s - 1550s 1560s 1570s 1580s 1590s
Years: 1537 1538 1539 1540 1541 - 1542 - 1543 1544 1545 1546 1547
... of oscillations per second (s-1, 1/s).
For example, red light has a frequency of about 4.6×1014 Hz. The unit is named in honor of the German physicist ...
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