Cardiovascular System
A bedridden patient (whose mass is 60 kg) is lying on a firm mattress so that the area of contact between the mattress and the patient’s bony prominences (shoulders, buttocks and heels) is 600 cm2. Given that pressure is force divided by area, and that the acceleration due to gravity is 10 m/s2, what is the pressure (in kPa) that would be experienced by the bony prominences?
1 kPa
10 kPa
100 kPa
600 kPa
10 kPa
P = (60 ร 10)N รท 0.06 m2 = 10,000 Pa = 10 kPa
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