Question

the train Travels at a speed of 60 km for 0.52 hour at 30 km per hour for the next 0.24 and then at 70 kilometre per hour for the next 0.71 per hour what is the average is trains​

Answer 1

Answer:

☆Given :-

First speed, v₁ = 60 km/h

Time taken for this part of trip, t₁ = 0.52 h

Second speed, v₂ = 30 km/h

Time taken for this part of trip, t₂ = 0.24 h

Third speed, v₃ = 70 km/h

Time taken for this part of trip, t₃ = 0.71 h

☆ Calculate :-

Average speed, V(avg) = ???

☆Formula to be used :-

Distance = Speed × Time

V(avg) = Total distance/Total time taken

☆Solution :-

Now, in this case we are not given the total distance traveled. so first of all we will find out the distance covered during the three given intervals by using the formula,

Distance = Speed × Time

(i) 1st part, d₁ = v₁ × t₁ = 60 × 0.52 = 156/5 km

(ii) 2nd part, d₂ = v₂ × t₂ = 30 × 0.24 = 36/5 km

(iii) 3rd part, d₃ = v₃ × t₃ = 70 × 0.71 = 497/10 km

Total distance, d = d₁ + d₂ + d₃

= 156/5 + 36/5 + 497/10 = 881/10 = 88.1 km

Total time taken, t = t₁ + t₂ + t₃

= 0.52 + 0.24 + 0.71 = 1.47 h

Now,

V(avg) = Total distance/Total time taken

⇒ V(avg) = 88.1/1.47

⇒ V(avg) = 59.93 km/h.

Hence, the average speed of the train is 59.93 km/h.