Question

A person measures his or her heart rate by counting the number of beats in 30s. If 40±1 beats are counted in 30.0±0.5s, what is the heart rate and its uncertainty in beats per minute?

Answer 1

Answer:

$Rate = 1.33 \pm 0.055$ beats per second

Explanation:

Number of heart beats = $40 \pm 1$

time taken = $30.0 \pm 0.5 s$

now we have

$N = 40 \pm 2.5$%

$t = 30.0 \pm 1.67$%

now rate of heart beat is defined as number of heart beat per unit of time

so we have

$Rate = \frac{N}{t}$

$Rate = \frac{40 \pm 2.5}{30 \pm 1.67}$

so we have

$Rate = 1.33 \pm (2.5 + 1.67 )$

$Rate = 1.33 \pm 4.17$%

$Rate = 1.33 \pm 0.055$ beats per second