Question

6. A train first travels for 30 min with a velocity
30 km h-1 and then for 40 min with a velocity
40 km h-' in the same direction, Calculate : (i) the total
distance travelled, (ii) the average velocity
of the train.​

Answer 1

Answer:

total distance =41.66 kms; average velocity = 35.7 km/hr

Explanation:

we know,

              the train travels for  

                30 mins with speed 30 km/hr

        and  

                40 mins with speed 40 km/hr

now,

        time in first case = 30 mins = 30/60 hrs = 1/2 hrs

        time in second case = 40 mins= 40/60 hrs= 2/3 hrs

     i.e, total time = 1/2 + 2/3 = 7/6 hrs

           then,

                   distance in first case =  velocity * time

                                                      = 30*(30/60) = 15 kms

                   distance in second case = velocity * time

                                                      = 40*(40/60) = 26.66 kms

i.e, total distance= 15 + 26.66 = 41.66 kms    

now,

       average velocity = total distance/ total time

      i.e, average velocity = 41.66/7 * 6

            average velocity = 35.7 kms/hr

thank you

hope this helped

hail hydra.