Question

A car travels along a straight road to the east for

100 meters in 4 seconds, then has to turn around

and goes back west for 50 meters in 1 second.

Determine average speed and average velocity.

Answer 1

Answer: 90 m/s, 70 m/s

Step-by-step 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
`100* 4=400\ m`

Distance traveled in the west is
`50* 1=50\ m`

Total distance
`=400+50=450\ m`

total displacement
`=400-50=350\ m`

total time
`t=4+1=5\ s`

Average speed

`\Rightarrow s_(avg)=\frac{\text{distance}}{\text{time}}=(450)/(5)\\\\\Rightarrow s_(avg)=90\ m/s`

Average velocity

`\Rightarrow v_(avg)=\frac{\text{displacement}}{\text{time}}=(350)/(5)\\\\\Rightarrow v_(avg)=70\ m/s`