Velocity and Speed
The average velocity `v_(x,avg)` of an object is defined as the object’s `displacement` `∆x` divided by the time interval `∆t` during which that displacement occurs:
`v_(x,avg)=(∆x)/(∆t)`
`a v e r a g e\ v e l o c i ty = (d i s p l a c e m e n t)/(r e q u i r e d\ t i m e)`
The average speed `v_(avg)` of an object, a scalar quantity, is defined as the total distance `d` traveled divided by the total time interval required to travel that distance:
`v_(avg)=d/(∆t)`
`a v e r a g e\ s p e e d = (d i s t a n c e\ t r a v e l e d)/(r e q u i r e d\ t i m e)`
From Example 1:
Average velocity of the car from A to F:
`∆x = -53 m - 30 m = -83 m`
`∆t = 50s-0s = 50s`
`v_(x,avg)=(∆x)/(∆t)=(-83m)/(50s) = -1.7 m//s`
Average speed of the car from A to F:
`d_(a->f) = 127 m`
`∆t = 50s-0s = 50s`
`v_(avg)=d_(a->f)/(∆t)=(127m)/(50s) = 2.5 m//s`