On a velocity-time graph of a person's walk, if a person is slowing down in the positive direction, then acceleration is in the negative direction.For example, the positive direction is [E]. If a person's acceleration is -1m/s^2, then it is 1 m/s^2 [West]. But that doesn't make sense, since the person is still walking east, but slowing down.
To slow down a person moving East, you push West.
F = m A
Thanks!
In the scenario you described, where a person is walking in the east direction and slowing down, the velocity-time graph would show a positive velocity initially and then decreasing towards zero.
The confusion might arise from the concept of acceleration, which is the rate at which velocity changes. When a person is slowing down, the velocity is decreasing, which means the change in velocity is negative. Therefore, the acceleration is negative.
However, it is important to note that acceleration represents the change in velocity, not the direction of motion. In this case, although the person is slowing down, they are still walking in the east direction, as indicated by the positive portion of the velocity-time graph. The negative acceleration simply indicates that the person's velocity is decreasing.
So, to summarize, if a person is slowing down in the positive direction (e.g., walking east), the velocity will be positive but decreasing, and the acceleration will be negative. The negative acceleration doesn't indicate a change in direction; rather, it signifies a decrease in velocity.