a particle moves 1/3rd of the distance in aspeed of 6km/hr and rest with a speed of 18km/hr.find the average speed?
To find the average speed, we need to consider the total distance covered and the total time taken.
Let's assume that the total distance is D.
The particle covers 1/3rd of the distance at a speed of 6 km/hr, which means it travels (1/3)D in this time. To find the time taken for this part, we can use the formula:
Time = Distance / Speed
Time = (1/3)D / 6 km/hr
Time = (1/18)D
The particle covers the remaining 2/3rd of the distance at a speed of 18 km/hr, which means it travels (2/3)D in this time. To find the time taken for this part, we can use the formula:
Time = Distance / Speed
Time = (2/3)D / 18 km/hr
Time = (1/27)D
The total time taken is the sum of the individual times:
Total Time = (1/18)D + (1/27)D
Total Time = (3 + 2) / 54 D
Total Time = (5/54)D
The average speed is given by the formula:
Average Speed = Total Distance / Total Time
Average Speed = D / (5/54)D
Average Speed = 54/5 km/hr
Average Speed = 10.8 km/hr
Therefore, the average speed of the particle is 10.8 km/hr.