Auniform pole is propped between the floor and the ceiling of a room. the height of the room is 7.11 ft, and the coefficient of static friction between the pole an the ceiling is 0.671. the coefficient of static friction between the pole and the floor is greater than that between the pole and the ceiling. for parts () assume the mass of the pole is 3.1 ibm and its length is 7.71 ft. give your answers in pounds of force (lbf). (a) find the weight of the pole. w - + (b) find the normal force on the pole from the ceiling. n = + (c) find the frictional force from the ceiling. y + (d) find the normal force from the floor n = 9 + (e) find the frictional force from the floor f = y + for part (f), assume you can make the pole any way you like, out of any material, with any radius and any length. (f) what is the length of the longest pole that can be propped between the floor and the ceiling (in feet)?

There is a theory that indicates that dinosaurs became extinct when about 65 million years ago, a large asteroid hit the earth surface. dust caused by this collision blocked the sunlight reaching the earth's surface and many forms of life became extinct due to the cold. fearing this threat, how large the radius of an asteroid should you be looking for if the dangerous asteroid size is approximately the same as the one that killed the dinosaurs? available data suggests that about 18% of that asteroid's mass ended up as a dust spread evenly over earth after eventually settling out of the upper atmosphere. about 0.0180 g/cm^2 of dust, which is chemically different than the earth's rock, covered the earth's surface. typical asteroids have a density of about 1.9 g/cm^3. now that we know the size of the asteroid, how much energy was released during impact, assuming all of it was just the kinetic energy of the asteroid right before the impact?

Part 1: a magnetic levitation or maglev train rides rails without touching them. explain how this works using your data. include the appropriate magnet drawing in your answer. part 2: two objects are near a bar magnet. one is about 1 cm away, while the other is 6 cm away. compare and contrast the magnetic force that affects each object. use your data to answer the question

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy