Final answer:
The time it takes for trucks A and B to completely pass each other is approximately 1.67 seconds.
Step-by-step explanation:
To determine the time it takes for two trucks to completely pass each other, we need to calculate the relative speed at which they are approaching each other. Truck A is traveling at 28 km/hr, while Truck B is traveling at 26 km/hr. To find the relative speed, we add their velocities together: 28 km/hr + 26 km/hr = 54 km/hr.
The distance that needs to be covered to completely pass each other is the sum of the lengths of both trucks: 10 m + 15 m = 25 m.
To convert the relative speed from km/hr to m/s, we divide by 3.6: 54 km/hr ÷ 3.6 = 15 m/s.
Finally, we can calculate the time it takes to cover the distance by dividing the distance by the relative speed: 25 m ÷ 15 m/s = 1.67 s.
Therefore, it takes approximately 1.67 seconds for the trucks to completely pass each other.