4–15. the post is made of douglas fir and has a diameter of 100 mm. if it is subjected to the load of 20 kn and the soil provides a frictional resistance that is distributed along its length and varies linearly from w = 4 kn> m at y = 0 to w = 12 kn> m at y = 2 m, determine the force f at its bottom needed for equilibrium. also, what is the displacement of the top of the post a with respect to its bottom b? neglect the weight of the post.

The image shows a pendulum in simple harmonic motion the pendulum starts at a and swing to e

Sawyer is studying diffraction. he draws a diagram of a plane wave to show how light waves travel. which best describes sawyer’s error? the wave fronts should be perpendicular to the direction in which the waves move. the arrow showing the direction of movement of the waves should be pointing to the left. the arrow showing the direction of movement of the waves should be pointing downward. the wave fronts should be both parallel and perpendicular to the direction in which the waves move.

How would a small bar magnet be oriented when placed at position x?