A person starts walking along a straight line from point A to point B with a constant speed of 2.3 m/s. At point B, it turns and returns to point A with a speed of 1.1 m/s. What will be his average speed in m/s for the entire journey?
what is its average speed in m/s?
Ответы
Ответ:
To find the average speed for the entire journey, we need to calculate the total distance traveled and divide it by the total time taken. Let's assume the distance between point A and point B is d.
When the person walks from point A to point B at a speed of 2.3 m/s, the time taken is t1 = d/2.3.
Upon turning at point B and returning to point A with a speed of 1.1 m/s, the time taken is t2 = d/1.1.
The total time for the entire journey is T = t1 + t2 = (d/2.3) + (d/1.1) = (1.1d + 2.3d)/(2.3 * 1.1).
The total distance traveled for the round trip is 2d.
Therefore, the average speed (S) is given by the formula S = Total distance / Total time = 2d / T.
Substituting the values, we get S = (2d) / ((1.1d + 2.3d)/(2.3 * 1.1)).
Simplifying the expression, we find that S = (2 * 2.3 * 1.1)/(1.1 + 2.3) ≈ 1.517 m/s.
Therefore, the person's average speed for the entire journey is approximately 1.517 m/s.