(a) An automobile having a mass of 900 kg initially moves along a level highway at 100 km/h relative to the highway. It then climbs a hill whose crest is 50 m above the level highway and parks at a rest area located there. For the automobile, determine its changes in kinetic and potential energy, each in kJ. For each quantity, kinetic energy and potential energy, specify your choice of datum and reference value at that datum. Let g = 9.81 m/s².

1. An object of mass 150 kg is dropped from a height of 400 m with no initial velocity. The body encounters an air resistance proportional to its velocity. If the limiting velocity is known to be 100 m/s, find an expression for the velocity v (in m/s) of the body at any time t (in seconds). Use g = 9.8 m/s². v = 100( 1– e -0.047t B) v = 100[ 1- e -0.085: -0.0231 C) v = 100| 1-e D) v = 100 -0.0981 -e

Nhand,A 75 N ma = 3 kg %D VA = 8 m/s Block Block Block Block B A Hx = 0.4 %3D 2 m Ax Note: Diagram is not drawn to scale A hand pushes block A (m,= 3 kg) with a constant force Nand. A= 75 N for a distance Ax 2 m along a (mostly) frictionless table such that it speeds up from rest and is traveling at a speed of 8 m/s after it slides over a rough section of the table (H = 0.4). Block A then collides with a more massive block B (mg = 6 kg) that is initially at rest. Find the speed of block A after it has been released by the hand and just before the rough section of the table. A) 10 m/s B) 20 m/s C) 30 m/s D) 40 m/s E) 50 m/s O A O B O D O E

WITH FRICTION Find the downward acceleration of ml if it has a mass of 40.9 kg and the kinetic coefficient of friction of m2 and m3 to the surface has the same value of 0.2. 5.00 kg T 3.00 kg 173 25.0° Select one: Oa 11.9831 m/s^2 ob 76410 m/s^2 Oc 15.7184 m/s^2 Od 40749 m/s^2