Question

Redraw Fig. 3.11a if$\overrightarrow{\mathbf{a}}$is antiparallel to$\overrightarrow{\mathbf{v}}$. Does the particle move in a straight line? What happens to its speed?

Short answer

The acceleration and the velocity are antiparallel the velocity will decrease.

Step-by-step solution

Concept/Significance of Acceleration.

The rate at which an object's velocity changes with respect to time is called acceleration. Newton's Second Law states that an object's acceleration is the net effect of all forces acting on it.

Determination of

The redrawn figure for 3.11a is given by,

The particle's acceleration runs counter to its velocity. The particle's speed slows as a result.

Particles will travel in a straight path because$\overrightarrow{a}$ and$\overrightarrow{v}$ are antiparallel. When a particle's speed approaches zerospeed will be slowed down, it retraces its journey only if the acceleration is in the same direction.

Thus, if the acceleration and the velocity are antiparallel the velocity will decrease.