During strenuous exercise a heart beats 150 times per minute. What is the time taken for one beat?

1. Frequency must first be put into beats per second: 150 beats / 60 s = 2.50 Hz. 2. Period is the reciprocal of frequency, T = 1 / f. 3. T = 1 / 2.50 Hz = 0.400 s per beat. 4. Quoting 2.50 s inverts the arithmetic and would mean a heart rate of 24 beats per minute. 5. Leaving the rate in beats per minute without converting gives 150 s, which is over two minutes for one beat. _Source: OpenStax College Physics (CC BY 4.0), Ch 16 "Oscillatory Motion and Waves", section 16.2 Period and Frequency in Oscillations_