Question

If a material point moves in the negative direction of the ox axis (has a negative velocity) and then stops, what is its acceleration? What is the projection of acceleration on the direction of travel?

Answer 1

Ответ:

Acceleration is positive though its projection would be negative

Объяснение:

Answer 2

If a material point moves in the negative direction of the x-axis (which we can assume is a one-dimensional coordinate system) and then stops, it means its velocity is decreasing in the negative x-direction until it becomes zero. This change in velocity over time indicates that the point is experiencing a deceleration or negative acceleration.

Acceleration is defined as the rate of change of velocity with respect to time. Mathematically, acceleration (a) can be calculated as:

$a = \frac{\Delta v}{\Delta t}$

Where $\Delta v$ is the change in velocity and $\Delta t$ is the change in time.

In this case, the point is slowing down until it comes to a stop. So, $\Delta v$ is the initial velocity in the negative direction (negative because it's moving in the negative x-axis) and $\Delta t$ is the time it takes to stop.

The projection of acceleration on the direction of travel (x-axis) is equal to the acceleration itself because the point is only moving along the x-axis and the negative sign indicates the direction (negative x).

So, the acceleration is negative (deceleration) and its projection on the direction of travel is also negative (in the negative x-direction).