A student walks 4 m in the positive direction in 4 s, stands still for 2 s, then walks 4 m farther in the positive direction in 4 s. The graph shown is offered for the walk. What is the flaw?
A boat crosses to an island dock: it holds a steady 4 m/s for 3 s, then sits at rest at the dock for the next 3 s. A classmate offers this drawing of the trip.
The drawing says something the boat never did. What does it claim?
Judge an offered velocity-time graph exactly as you judged offered position-time graphs: check the description against the graph, one stage at a time.
Stage 1 says a steady 4 m/s for 3 s. The offered first segment sits flat at 4 m/s until t = 3 s. That stage matches.
Stage 2 says at rest. At rest is v = 0 m/s: a segment lying ON the time axis. The offered stage 2 is a ramp from 4 m/s down to zero, above the axis almost to the end. The ramp claims the boat spends all 3 s still moving, only reaching rest at t = 6 s. That is the flaw.
A runner runs at a steady velocity in the positive direction for 6 s. The graph shown is offered for the run. What is the flaw?
The description says the velocity is steady, so the graph should be one flat segment at that velocity.
The offered line rises from 0 to 6 m/s. On a velocity-time graph, a rising line claims the runner speeds up from rest.
This rising line is the position-time shape for a steady run, drawn on the wrong graph.
The flaw is the rising segment: it claims steady speeding up, and a steady velocity needs a flat segment at its level.
A taxi holds a steady 6 m/s for 2 s, then is at rest for 4 s. The graph shown is offered for this trip. What is the flaw?
A drone flies at a steady 4 m/s in the positive direction for 5 s. The graph shown is offered for the flight. What is the flaw?
A kayak cruises at a steady 5 m/s in the negative direction for 4 s. The graph shown is offered for the cruise. What is the flaw?
The flat shape is right: a steady velocity is a flat segment.
But the segment sits above the time axis, claiming motion in the positive direction.
Negative-direction motion sits below the axis: the correct segment is flat at −5 m/s.
The flaw is the side of the axis: the kayak's segment must lie at −5 m/s, below the time axis.
A swimmer swims at a steady 3 m/s in the negative direction for 6 s. The graph shown is offered for the swim. What is the flaw?
A tractor brakes steadily from 9 m/s to rest over 3 s, then stays at rest for 3 s. The graph shown is offered for this stop. What is the flaw?
A cart slows steadily from 8 m/s, reverses direction at t = 4 s, and reaches -4 m/s at t = 6 s. The graph shown is offered for this motion. What is the flaw?
A car accelerates steadily from rest for 3 s, then holds its top speed for 3 s. The graph shown is offered for this trip. What is the flaw?