The following statements describe stages of a high-speed maglev train test run along a straight horizontal track:
Stage A: The train accelerates at a constant rate from 0 m/s0\text{ m/s}0 m/s to 60 m/s60\text{ m/s}60 m/s in 40 s40\text{ s}40 s.
Stage B: The train travels at a constant velocity for 240 s240\text{ s}240 s.
Stage C: The train decelerates at a constant rate, coming to a complete stop in 50 s50\text{ s}50 s.
During which stage of the journey is the resultant force on the train zero?
A velocity-time graph of this journey is plotted with time in seconds on the horizontal axis and velocity in metres per second on the vertical axis. The line for Stage A starts at (0,0)(0, 0)(0,0) and ends at (40,60)(40, 60)(40,60). Describe the lines that must be drawn to complete the graph for Stage B and Stage C, specifying their start and end coordinates.
Write down the equation which links acceleration, change in velocity, and time taken.
During another trial, the train accelerates at 2.25 m/s22.25\text{ m/s}^22.25 m/s2 for 18.0 s18.0\text{ s}18.0 s. Calculate the increase in velocity of the train.