an object moves from point p to q with an average speed of 60m/s and comes back from point q to p with an average speed of 144km/h . what is the average speed of whole journey in m/s?

average speed is 48 m/s

144km/h = 144,000m/3600s = 40 m/s.

V = (60+40)/2 = 50 m/s.

144km/h = 144,000m/3600s = 40 m/s.

V = (60+40)/2 = 50 m/s

To find the average speed of the whole journey in m/s, we need to calculate the total distance traveled and the total time taken for both legs of the journey.

Let's start by converting the average speed of the return journey from km/h to m/s:
1 km/h = (1000 m / 3600 s) = 0.2778 m/s

Hence, the average speed of the return journey in m/s is 144 km/h × 0.2778 m/s = 40 m/s.

Now, let's calculate the total distance traveled. Since the object moves from point P to Q and then comes back from Q to P, these two distances cancel each other out. Therefore, the total distance traveled is zero.

Finally, let's calculate the total time taken for the whole journey. Since the object moves from point P to Q and then comes back to P, we can simply add the time taken for both legs.

Let the time taken for the outward journey (from P to Q) be t1, and the time taken for the return journey (from Q to P) be t2.

The average speed is defined as total distance divided by total time. Since the total distance is zero, the average speed is also zero:

Average Speed = Total Distance / Total Time
= 0 / (t1 + t2)
= 0

Therefore, the average speed of the whole journey is 0 m/s.