Intro to Motion (Kinematics) Video Lessons

Concept

Problem: Which of the following situations is impossible? And why?a) An object has velocity directed east and acceleration directed east.b) c) An object has velocity directed east and acceleration directed west.c) An object has a constant non-zero velocity and changing acceleration.d) An object has a constant non-zero acceleration and changing velocity.e) An object has zero velocity but non-zero acceleration.If an object stops moving at a point. Then must its acceleration be zero at that point? Why? or why not?

FREE Expert Solution

Acceleration:

$\overline{){\mathbf{a}}{\mathbf{=}}\frac{{\mathbf{v}}_{\mathbf{f}}\mathbf{-}{\mathbf{v}}_{\mathbf{0}}}{\mathbf{∆}\mathbf{t}}}$

a)

For the particle to be in the same direction and increasing velocity, we must have:

vf - v0 > 0

This implies that a > 0

Option a) is possible and the motion is acceleration motion.

Problem Details

Which of the following situations is impossible? And why?

a) An object has velocity directed east and acceleration directed east.

b) c) An object has velocity directed east and acceleration directed west.

c) An object has a constant non-zero velocity and changing acceleration.

d) An object has a constant non-zero acceleration and changing velocity.

e) An object has zero velocity but non-zero acceleration.

If an object stops moving at a point. Then must its acceleration be zero at that point? Why? or why not?