A viking sails from his home port and travels east at 15km/hr.after 10 hours, the wind change and he is blown south west at 20km/hr for six hours.at his point wind drops, the ship is becalmed and doesnot move for the next ten hours.becoming tired of waiting,the viking order his crew to start rowing west at 10km/hr which they do for five very tiring hours before beaching the ship on a convenient island. calculate the average velocity and average speed of the ship from when its left port to when it was beached.
5KM/H
average speed is 10.3kmh
15km/h for ten hours is 150km
20km/h for 6 hours is 120km
10km/h for 5 hours is 50km
10hrs at rest
150+120+50=320km in 31hrs
Speed average=total distance travelled/time taken
320/31= Average speed of the ship is 10.3km/h
currently trying to work out the displacement to work out the average velocity cause v=d/t we already have time
To calculate the average velocity and average speed of the ship, we need to first find the total displacement (distance and direction) of the ship during its journey.
1. Eastward Travel:
The ship sails east at 15 km/hr for 10 hours. So, the distance traveled in this leg is:
Distance = Speed * Time = 15 km/hr * 10 hrs = 150 km east.
2. Southwest Wind Blowing:
The ship is blown southwest at 20 km/hr for 6 hours. The resultant displacement due to this leg is a combination of southwest and east directions. Using vector addition, we find:
Distance = Resultant Speed * Time = 20 km/hr * 6 hrs = 120 km southwest.
3. Becalmed (No Movement):
The ship doesn't move during this period, which means there is no displacement in any direction. Therefore, the distance is 0 km.
4. Rowing Westward:
The ship rows west at 10 km/hr for 5 hours. So, the distance traveled in this leg is:
Distance = Speed * Time = 10 km/hr * 5 hrs = 50 km west.
Adding up the respective displacements, we get a total displacement of:
Total Displacement = 150 km east - 120 km southwest + 0 km - 50 km west
Total Displacement = 80 km east - 170 km southwest
Now, to calculate the final answer:
Average Velocity = Total Displacement / Total Time
Total Time = Time for Eastward Travel + Time for Southwest Wind Blowing + Becalmed Time + Time for Rowing Westward
Total Time = 10 hrs + 6 hrs + 10 hrs + 5 hrs
Total Time = 31 hrs
Average Velocity = (80 km east - 170 km southwest) / 31 hrs
To find the average speed, we need to calculate the total distance traveled during the complete journey:
Total Distance = Distance for Eastward Travel + Distance for Southwest Wind Blowing + Becalmed Distance + Distance for Rowing Westward
Total Distance = 150 km east + 120 km southwest + 0 km + 50 km west
Total Distance = 320 km
Average Speed = Total Distance / Total Time
Average Speed = 320 km / 31 hrs
Therefore, Average Velocity = (80 km east - 170 km southwest) / 31 hrs
And Average Speed = 320 km / 31 hrs