Answer
(a) average acceleration:
magnitude: $1.0~m/s^2$
algebraic sign: negative
direction: to the left
(b) average acceleration:
magnitude: $1.0~m/s^2$
algebraic sign: negative
direction: to the left
(c) average acceleration:
magnitude: $3~m/s^2$
algebraic sign: negative
direction: to the left
Work Step by Step
average acceleration = $\frac{\Delta v}{\Delta t}$
(a) $\frac{\Delta v}{\Delta t} = \frac{5.0~m/s - 15.0~m/s}{10~s} = -1.0~m/s^2$
average acceleration:
magnitude: $1.0~m/s^2$
algebraic sign: negative
direction: to the left
(b) $\frac{\Delta v}{\Delta t} = \frac{-15.0~m/s - (-5.0)~m/s}{10~s} = -1.0~m/s^2$
average acceleration:
magnitude: $1.0~m/s^2$
algebraic sign: negative
direction: to the left
(c) $\frac{\Delta v}{\Delta t} = \frac{-15.0~m/s - 15.0~m/s}{10~s} = -3.0~m/s^2$
average acceleration:
magnitude: $3~m/s^2$
algebraic sign: negative
direction: to the left
