An object travels North at 4 m/s4ms for 9 s9s and then travels South at 1 m/s1ms for 6 s6s. What are the object's average speed and velocity?

1 Answer
Sep 8, 2017

The average speed is =2.8ms^-1=2.8ms1
The average velocity is =2ms^-1=2ms1

Explanation:

The total distance travelled is d=(4*9)+(1*6)=36+6=42md=(49)+(16)=36+6=42m

The total time is t=9+6=15st=9+6=15s

The average speed is

barv=d/t=42/15=2.8ms^-1¯v=dt=4215=2.8ms1

The displacement is

Deltax=(4*9)-(1*6)=36-6=30m

The average velocity is

=(Deltax)/t=30/15=2ms^-1