A boy walks a total distance of 210 km due North. His starting position is at 20 km and his final position is 34 km. If it takes him 3 hours and 20 minutes to make his trip, what is his velocity? What is his speed?
his velocity= change displacement/time=(34kmN-20kmN)/3 1/3 hrs
his speed= 210/ 3 1/3 km/hr
To determine the boy's velocity, we need to find the displacement and divide it by the total time taken. Velocity is a vector quantity, meaning it has both magnitude and direction. In this case, the direction is North.
Displacement is the change in position from the initial point to the final point. In this scenario, the boy moves from a starting position of 20 km to a final position of 34 km, traveling in a North direction. The displacement can be calculated as follows:
Displacement = Final position - Initial position = 34 km - 20 km = 14 km North
Now, let's convert the time taken to hours to ensure consistent units:
3 hours and 20 minutes = 3 + (20/60) = 3.33 hours
Now, we can calculate the boy's velocity:
Velocity = Displacement / Time = 14 km / 3.33 hours ≈ 4.20 km/h North
The velocity is approximately 4.20 km/h North, where North represents the direction.
Next, let's find the boy's speed. Unlike velocity, speed is a scalar quantity, meaning it only has magnitude and no specific direction. To calculate speed, we divide the total distance traveled by the total time taken:
Speed = Total distance / Time = 210 km / 3.33 hours ≈ 63.06 km/h
The boy's speed is approximately 63.06 km/h, representing only the magnitude of the distance traveled per unit of time.