At a resting pulse rate of 77 beats per minute, the human heart typically pumps about 65 mL of blood per beat. Blood has a denstity of 1060 kg / m3. Circulating all of the blood in the body through the heart takes about 1 min for a person at rest. (a) How much blood is in the body? (b) On average, what mass of blood does the heart pump with each heart beat?

Verified Answer :

Given:
1 minute circulation
77 beats per minute
65 ml of blood per beat
blood density of 1060kg/m³

a) how much blood is in the body?

77 beats per min 65ml per beat = 5,005 ml per minute

5,005ml
1l/1000ml = 5.0005 Liters.

I'm not sure on how to solve for question b.

Answer:

(a) Blood in the body is 7765 = 5005 ml

(b) On average, mass of blood does the heart pump with each heart beat is 68.9 g

Step-by-step explanation:

Given : At a resting pulse rate of 77 beats per minute, the human heart typically pumps about 65 mL of blood per beat. Blood has a denstity of 1060 kg / m3. Circulating all of the blood in the body through the heart takes about 1 min for a person at rest

To Find:  (a) How much blood is in the body?

(b) On average, what mass of blood does the heart pump with each heart beat?

Solution :

Since we are given that heart beats per minute =77

And Heart pumps about 65 mL of blood per beat

(a) So, blood in the body is 7765 = 5005 ml

Since mass = volume density

⇒ so,  mass of blood does the heart pump with each heart beat = volume density

⇒mass =  \(65 ml *1060kg/m^{3}\)

\(1ml = 10^{-6} m^{3}\)

Thus 65 ml =  \(65*10^{-6} m^{3}\)

⇒mass =  \(65*10^{-6} m^{3} *1060kg/m^{3}\)

⇒mass =  \(68900*10^{-6}\)

⇒mass =  \(689*10^{-4}\)

⇒mass =  \(689*10^{-3}*10^{-1}\)

⇒mass =  \(68.9*10^{-3} kg\)

⇒mass =  \(68.9grams\)

(b) On average, mass of blood does the heart pump with each heart beat is 68.9 g