Usha swims in a 90 m long pool. She covers 180 m in one minute by swimming from one end to the other and back along the same straight path. Find the average speed and average velocity of Usha.

Explanation

Total distance covered by Usha in 1 min is 180 m.
Displacement of Usha in `1 min =0 m `
Average speed `= (" Total distance covered")/("Total time taken") = (180m )/(1 mn)`
`= (180 m)/(1 min ) x (1 min)/(60 s)`
`= 3 ms ^(-1)`
Average velocity `= ("Displacement")/("Total time taken") = (0m)/(60s ) = 0 m s ^(-1)`
The average speed of Usha is `3 ms ^(-1) and ` her average velocity is `0 ms ^(-1).`