A car moves for half of its time at `80 km//h` and for rest of time at `40 km//h`. Total distance covered is `60km`. What is the average speed of the car

Options

A. `60 kmh^(-1)`
B. `80 kmh^(-1)`
C. `120 kmh^(-1)`
D. `180 kmh^(-1)`

Answer

A

Explanation

`upsilon_(av)=("Total displacement")/("Total time")=(80t+40t)/(2t)=60 kmh^(-1)`