Question

A cheetah starts at x = 0 and a gazelle starts at x = 0.5 km. The cheetah starts running straight towards the gazelle at steady speed 80 km/hr (he’s tired) and, at the same instant, the gazelle runs straight away from the cheetah at steady speed 60 km/hr. Draw a reasonable graph with the position x vertically and the time t horizontally, including vertical and horizontal tic marks (you can use km and hr as the units if you wish, but the slopes must each be about right, and the tic marks on the axes must be evenly spaced). Simply from the graph, determine when and where the cheetah catches the gazelle. Then, start with the definition of velocity and use mathematics to determine when and where (units of seconds and meters) the cheetah catches the gazelle; show all of the mathematical steps and use words to explain.

3. (Individual, 10 points for correctness) A car goes from 0 to 60 miles per hour during a time of 11 seconds. Assuming constant acceleration, starting with one or more of the four equations given in class, and showing the mathematics, calculate the acceleration (in m/s2) and the distance travelled (in m) during that 11 seconds.

Answer 1