Calculating Work and Power in Two Common Problems: Bubble Radius & Heart Pumping

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The discussion focuses on calculating work and power in two scenarios: inflating a spherical bubble and the heart's pumping action. For the bubble, the work done is determined using the formula involving the change in surface area and the superficial tension of 26 N/m. In the heart pumping scenario, the power is calculated by considering the volume of blood pumped per beat, the pressure exerted, and the heart rate of 65 beats per minute. Participants emphasize the importance of adhering to forum guidelines for effective communication. Accurate calculations are crucial for understanding these physical processes.
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1. There's an spheric bubble in the air with a radius of 3.2 cm. You blow air inside the bubble until its radius gets 5.8 cm. Which is the work done on the bubble? Consider the (constant) superficial tension of the bubble as 26 N/m.

2. The heart pumps 75 ml of blood in each beating with an average pressure of 110 mmHg. It beats 65 times per minute. Calculate the power of pumping of the heart.
 
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