A spring extends 7 cm to the ground and back again 20 times a minute. What is the period?
- 0.3 hertz.
- 3 seconds.
- 1/3 cycle.
Explanation from PART66Online
The spring completes one full cycle (down and back) 20 times per minute, giving a frequency of 20/60 = 1/3 Hz. The period is the reciprocal of frequency, T = 1 / (1/3) = 3 seconds. The 0.3 hertz option states a frequency, not a period, and answers the wrong quantity.
5
5rain asked · 5 Sep 2013
how it can be?
Community Comments (2)
P
PART66Online
5 Sep 2013
20 times per 60 seconds, so 1 period = 60 / 20 = 3.
S
Syed
19 Apr 2017
Thanks
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