Question

Calculate the amount of work (in Joules) required for your heart to pump one 0.961 liter of blood a vertical distance of 0.314 meters from your heart to your head. Assume that the density of blood is 1.06 g/cm3. You will need the conversion 1 \text{mL} = 1\text{cm}^{3}1mL=1cm ​3 ​​

Answer 1

Answer:

The amount of work required for the heart is: 3.14 Joules

Explanation:

We need to remember that the work done for a pump with constant pressure will be:$W=P*(V_{2}- V_{1})$, where W is the work, P is pressure and V is volume (change of the volume). Now we need to find the pressure. Using the Pascal's law ($P=p*g*h$), where P is pressure, p is density, g is the gravity and h is the height of the fluid's column and replacing the values given, we can find the pressure:$P_{blood} =1060*9.81*0.314=3265(N/m^{2})$. Then using the work's equation and replacing the value obtain for the pressure and the volume we get:$W_{heart}=P_{blood} *V_{heart(pump)} =3265*0.000961=3.14(Joules)$.