A hiker starts from a camp and walks due north for 3.0 km in 45 min. He then turns back and walks due south for 30 min with the same constant speed as before but stops when he is still 1.0 km north of the camp.
(i) Draw a qualitative position–time graph for the hiker’s motion, marking clearly the starting point, the turning point, and the final point.
(ii) Calculate the hiker’s net displacement from the camp at the end of the 75 min journey, stating its direction.
(iii) Determine the total distance walked and hence find the average speed for the entire trip.
(iv) Determine the magnitude and direction of the average velocity for the entire trip.
(v) Find the ratio of the average speed to the magnitude of the average velocity for this journey and comment on its numerical value.