Answer:
86.51° North of West or 273.49°
Explanation:
Let V' = velocity of boat relative to the earth, v = velocity of boat relative to water and V = velocity of water.
Now, by vector addition V' = V + v'.
Since v' = 6.10 m/s in the north direction, v' = (6.10 m/s)j and V = 100 m/s in the east direction, V = (100 m/s)i. So that
V' = V + v'
V' = (100 m/s)i + (6.10 m/s)j
So, we find the direction,Ф the boat must steer to from the components of V'.
So tanФ = 6.10 m/s ÷ 100 m/s
tanФ = 0.061
Ф = tan⁻¹(0.061) = 3.49°
So, the angle from the north is thus 90° - 3.49° = 86.51° North of West or 270° + 3.49° = 273.49°
Answer:
A.) 1430 metres
B.) 80 seconds
Explanation:
Given that the train accelerates from rest at 1.1m/s^2 for 20s. The initial velocity U will be:
U = acceleration × time
U = 1.1 × 20 = 22 m/s
It then proceeds at constant speed for 1100 m
Then, time t will be
Time = distance/ velocity
Time = 1100/22
Time = 50 s
before slowing down at 2.2m/s^2 until it stops at the station.
Deceleration = velocity/time
2.2 = 22/t
t = 22/2.2
t = 10s
Using area under the graph, the distance between the two stations will be :
(1/2 × 22 × 20) + 1100 + (1/2 × 22 × 10)
220 + 1100 + 110
1430 m
The time taken between the two stations will be
20 + 50 + 10 = 80 seconds
2.5 percent is fresh and only one present is easy to get.
Answer:
The two main categories of boat hull designs are;
- Displacement Hull
- Planning Hull
Explanation:
<u>Displacement Hull</u>
This type of boat hull is designed to displace certain amount of water as it moves. This displacement enable it to insert its body into the water and continue to displace water from its was as it moves. The weight of water displaced is usually equal to the weight of the boat.
Displacement Hull and Speed
Because of the need to displace water from its path to enable it insert itself into the water body for movement, the speed is usually slow compared to planning hull boats.
Displacement Hull Types:
- Round bottomed hull boat: Their hulls are made to have a round bottom in order to displace water and move smoothly through it. It can move quietly at low speed. How ever, they require complex stabilizer to control them from banking.
- Multi hull boat: This type of hull design has a large and long beam that make it to be very stable on the water body. They usually have ends pointed downwards for proper insertion and displacement. However, they don't turn easily on small space due to their large beam requirement.
<u>Planning Hull</u>
Planning hull boats are designed to slide very fasly on the water surface with very little or no insertion. They require boat engines that operates at a very high revolution per minute(rpm).
When at rest, that is at zero speed, they behave like displacement hull boats but only a small amount of water is displaced a they are usually lighter.
Planning hull boats can operate in three modes:
- Displacement mode: This mode is used when planning hull boats move at extremely slow speed. At this mode, they push water side ways as they move.
- Planning mode: This mode is activated as the speed of the boat increases to enable it glide on the surface of the water.
- Plowing mode: This mode is reach when the bow of the boat is trusted up and suspended as it slides through the surface of the water at a very high speed
Planning Hull and Speed
The speed of planning hull boats is very high when compared to displacement hull boats. This high speed of operation is powered by high rpm engines to enable it slide on the surface of the water.
Planning Hull Types/Merit and Demerit
- Flat Bottom Hull: Their hull is flat bottom shaped and has a draft that supports its suspension on water on a stable manner. Suitable for stable water. However, it moves haphazardly on shaky water.
- Deep Vee Hull: It has a V-shape hull that points towards the water body. Its V-shape makes it glide through rough water surfaces more smoothly than the flat bottom hull. However, it requires more power to operate and easily banks during sharp turning.