The science lecture theatre of a college is ` 10 m` wide and has a dorr at a cormer. A science techer entres at `12 . 00` noon through the dorr and makes ` 8 rounds along the ` 10 m` wall back and forth during the period and finaal leaves the class room at ` 12 . 40 p.m. through the same door. Compute the averae speed and average velocity.

Explanation

Total distance travelled in ` 40 minutes`
`= 20 xx 8 = 160 m `
Average speed `= 160 // ( 40 xx 60) = 0 067 ms^(-1)`
At ` 12 . 00 noon he is at the door and at ` 12. 40p.m.` he is again at the same door, the displacement during the ` 40 mimute time linterval is zero . So average velocity ` =0` .