Question

Does the object represented in FIGURE Q1.4 have

a positive or negative value of a_x? Explain.

Short answer

Acceleration is defined as the rate of change of velocity with respect to time.

Step-by-step solution

Given :

The velocity vector is increasing gradually as it moves towards the right.

A quantity is a vector quantity if it possesses both magnitude and direction.

Answer:

• The object will accelerate if the magnitude of the velocity, speed, changes or the direction changes.
• From the figure, one can observe that the velocity vector is getting longer , therefore, the object is speeding up as it travels towards left.
• As per convention, the sign of the velocity is negative.
• Since acceleration is the rate of change of velocity, its direction will be the same as the direction of velocity.
• Therefore, the object has negative a_x.