Pregnancy dramatically affects the energetics of swimming for female dolphins. Dolphins have an approximately circular cross section and are very streamlined. A typical dolphin has a girth—the circumference at the widest part of the body—of 1.4 m and a drag coefficient of 0.090. Advanced pregnancy increases the girth to 1.7 m and, with a less streamlined shape, the drag coefficient to 0.22. Dolphins typically cruise at a speed of 3.4 m/s a.What will be the cruising speed of a pregnant dolphin if she swims with the same power output as before becoming pregnant?

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Static and Kinetic Friction

Kinetic friction comes into existence when there are moving surfaces means in other words we can say that the force which comes into existing between moving surfaces is known as kinetic friction.