Starting from a light post, you walk 77 m east to a house, turn around, and then slowly walk 33 m west to a tree. It took you 34 s from post to house and 45 s from store to tree. a. What is your average velocity and average speed for the entire trip? b. What is your average velocity and average speed from the house to the tree? (a) Compute the average acceleration during these time intervals: (i) = 0 tot (ii) 30s to (iv) t = 0 tot 10 s; 140 s; (iii) = 10s to 30 s; 40 s. (b) What is the instantaneous acceleration at t = 20 s and at t == 35s? v, (km/h) 60 50 40 30 20 10 t(s) 0 5 10 15 20 25 30 35 40 A caribou moving with constant acceleration passes two points 86.0 m apart in 5.9 s. Its speed as it passed the second point is 16.4 m/s. a) What is its speed as it passed the first point? b) What is its acceleration? c) 10 s, after passing the first point, how much distance has it travelled and what is its velocity at that point? An 8700-kg drone took off vertically from the ground with a constant upward acceleration of 2.83 m/s2. When it has reached a height of 560 m, its engines suddenly fail; the only force acting on it is now gravity. a) What is the maximum height reached? b) How much time will elapse after engine failure before the rocket comes crashing down the ground, and how fast will it be moving just before it crashes? c) Sketch a vs t, v vs t, and y vs t graphs of the rocket's motion from the instant of blast-off to the instant just before it strikes the ground. Thomas the train traveling at 24.8 m/s sights Percy the train 200 m ahead on the same track. Percy is traveling at 15.0 m/s in the same direction as Thomas. Thomas immediately applies the brakes and was able to slow down by 0.100 m/s2 while the Percy unknowingly continues with constant speed. Take x = 0 at the location of Thomas he applies the brakes. (a) Will there be a collision? (b) If so, how far from Thomas' initial position will it take place (c) On a single graph, sketch the positions of the Thomas and Percy as a function of time. An airplane is dropping food and water on an isolated disaster area. The pilot releases it at 150 m above the level ground when the plane is flying at 75 m/s in a direction 55 above the horizontal. How far in front of the people should the pilot release it so that the relief goods land at the point where they are stranded? A hose is used to shoot water at a burning building. The water has a speed of 25.0 m/s. Water takes 3.00 s to reach a building 45.0 m away. The hose is at ground level. (a) Find the angle above the horizontal that the water exits the hose. (b) Find the speed and acceleration of the water at the highest point in its trajectory. (c) How high above the ground does the water strike the building, and how fast is it moving just before it hits the building? Battle for Bakhmut. In the plains near Bakhmut, an M1A2 tank detected a T-14 enemy tank 3km away, behind terrain cover. The M1A2 fires at an angle of 15 degrees above the horizontal but the shell fell 450 meters short of the target. Both tanks are at the same level. At what angles should the M1A2 tank fire to hit the enemy?