Question

One car moving on a straight road covers one third of the distance with 20 km/h and rest with 60 km/hr the average speed is

Answer 1

Average speed = Distance / Time
= S / (t1 + t2)
= S / (S/(3*20) + 2S/(3 * 60) ……[∵ time = Distance / Speed]
= 1 / (1/60 + 2/180)
= 36 kmph
= 36 × 5/18 m/s
= 10 m/s

Average speed of car is 36 kmph (= 10 m/s)