A particle travels 10 km by speed 100 m/s and next 10 km by speed 50 m/s. Calculate its average speed ?

To calculate the average speed, we need to know the total distance traveled and the total time taken.

1. First, let's calculate the time taken for each part of the journey:

   • For the first 10 km at 100 m/s: Time = Distance / Speed = 10,000 m / 100 m/s = 100 seconds

   • For the next 10 km at 50 m/s: Time = Distance / Speed = 10,000 m / 50 m/s = 200 seconds

2. Now, let's add these times together to get the total time: Total Time = 100 seconds + 200 seconds = 300 seconds

3. The total distance traveled is 20 km (or 20,000 m).

4. Now, we can calculate the average speed: Average Speed = Total Distance / Total Time = 20,000 m / 300 s = 66.67 m/s

So, the average speed of the particle is 66.67 m/s.