Answer:
second one is correct that is right
Solution :-
Given :
Distance 1 = 30 km
Distance 2 = 70 km
We know that speed = distance/time
and, Average speed = total distance/total time taken
When the train acquired a speed of 30 km/hr, the time taken = 30/30 = 1 hour
Average speed = 9distance 1 + distance 2)/(time 1 + time 2)
AS time 2 or t2 is time taken for the second part of the journey of 70 km
⇒ 40 = 100/(1 + t2)
⇒ 40 + 40t2 = 100
⇒ 40t2 = 100 - 40
⇒ 40t2 = 60
⇒ t2 = 60/40
⇒ t2 = 1.5
So, t2 or time taken to travel the second part of the journey is 1.5 hours.
Speed of the second part of the journey = distance 2/time 2
⇒ 70/1.5
⇒ 46.666 km/hr or 46.7 km/hr.
Hence the answer is = 46.666 km/hr or 46.7 km/hr.
Hope it helped u if yes mark me BRAINLIEST!
Tysm!
:)
The difference between temperature and thermal energy is that temperature measures the average kinetic speed of molecule and thermal energy is the total kinetic energy of all particles in a given substance.
Average speed = (total distance covered) / (total time to cover the distance) .
Total distance = (80 + 50 + 40) = 170 km
Total time = (1 + 0.5 + 0.5) = 2 hours
Average speed = (170 km) / (2 hrs) = 85 km/hr .
Answer:corrosion (i believe)
Explanation: