A particle moves along a line with velocity that is positive and increasing on the…

MATHEMATICS · Single correct · A Level · Mathematics · Kinematics · Kinematics

Problem

A particle moves along a line with velocity

v(t)

that is positive and increasing on the interval

0<t<3

, equals

0

t=3

, and is negative and decreasing on

3<t<6

. Which of the following statements best describes the particle’s acceleration on

0<t<6

? (a) Acceleration is negative for

0<t<3

and positive for

3<t<6

. (b) Acceleration is positive for

0<t<3

and negative for

3<t<6

. (c) Acceleration is positive on

0<t<6

because the speed is increasing. (d) Acceleration is zero on

0<t<6

because velocity is “linear” on each sub-interval.