Question

Darin skateboarded to the north at 7 m/s. In 5 seconds, he slowed down to 6 m/s. What was his acceleration?

A.0.2 m/s2 north
B.-0.2 m/s2 north
C.5 m/s2 north
D.-5 m/s2 north

Answer 1

initial velocity (u)= 7m/s
time (t) = 5 seconds
final velocity (v) =6m/s
a=v-u/t
=6-7/5
= -1/5
= -0.2m/s2 north

Answer 2

(v-u)/t
=( 6-7)/5
=-1/5
=-.2m/s2
so the answer is B !!