Answer: 90 m/s, 70 m/s
Explanation:
Given
A car travels 100 m east for 4 seconds and then turn around
goes back west for 50m in 1 sec
Distance traveled in the east is [tex]100\times 4=400\ m[/tex]
Distance traveled in the west is [tex]50\times 1=50\ m[/tex]
Total distance[tex]=400+50=450\ m[/tex]
total displacement[tex]=400-50=350\ m[/tex]
total time [tex]t=4+1=5\ s[/tex]
Average speed
[tex]\Rightarrow s_{avg}=\dfrac{\text{distance}}{\text{time}}=\dfrac{450}{5}\\\\\Rightarrow s_{avg}=90\ m/s[/tex]
Average velocity
[tex]\Rightarrow v_{avg}=\dfrac{\text{displacement}}{\text{time}}=\dfrac{350}{5}\\\\\Rightarrow v_{avg}=70\ m/s[/tex]