One can think of a circle as an N-sided polygon where N is a very very large number. This is because as the number of sides of a polygon increases the shape of the polygon starts resembling that of a circle. In the light of this fact explain why the diffraction pattern produced by the aperture DOTS is made of alternating bright and dark circular bands. Hint: First determine the diffraction pattern produced by an N-sided polygon. Then figure out what would happen to the diffraction pattern if the number of sides N becomes very large.

Askydiver weighing 140 lb (including equipment) falls vertically downward from an altitude of 19,000 ft and opens the parachute after 18 s of free fall. assume that the force of air resistance, which is directed opposite to the velocity, is of magnitude 0.55|v| when the parachute is closed and is of magnitude 14|v| when the parachute is open, where the velocity v is measured in ft/s. assume that acceleration due to gravity has magnitude 32 ft/s/s; remember that weight is the product of mass and gravitational acceleration. (a) find the speed of the skydiver when the parachute opens. (b) find the distance fallen before the parachute opens. (c) what is the limiting velocity vl after the parachute opens? (d) determine how long the sky diver is in the air after the parachute opens. (e) plot the graph of velocity versus time from the beginning of the fall until the skydiver reaches the ground.

Chameleons catch insects with their tongues, which they can rapidly extend to great lengths. in a typical strike, the chameleon's tongue accelerates at a remarkable 220 m/s2 for 20 ms, then travels at constant speed for another 30 ms.

What energy transformations occur each time the skateboarder rolls up the ramp?