Calculating Force on Aircraft Carrier John F. Kennedy

In summary, the aircraft carrier John F. Kennedy has a mass of 7.4*10^7kg and travels at its top speed of 35 knots when its engines are providing 280000 hp of power. If 70% of the power is used to push the ship through the water, the remaining 30% is lost to water resistance. Therefore, the magnitude of the force of water resistance opposing the carrier's motion at this speed is equal to the force of the ship.
  • #1
Exuro89
34
1

Homework Statement


The aircraft carrier John F. Kennedy has mass 7.4*10^7kg. When its engines are developing their full power of 280000 hp, the John F. Kennedy travels at its top speed of 35 knots.

If 70% of the power output of the engines is applied to pushing the ship through the water, what is the magnitude of the force of water resistance that opposes the carrier's motion at this speed?


Homework Equations


P=F*v

The Attempt at a Solution



Not sure if I understand the question correctly. What I did was convert 35 knots into m/s which was 18.06m/s. I converted the power from hp to watts to get 208880000watts. I divided the watts by the velocity to get force. If this is correct, this would be the force of the boat and not the water correct? Would the resistance be the 30% that the force loses?
 
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  • #2
Apparently 30% of the power is lost in the drive train and propeller.
Take 70% of the power and use it in the formula to find F.
 
  • #3
Alright so couldn't I just find the total from what I did above, then dividing the power by the velocity to get force and then multiple that by .3 to get teh water resistance? 70% is going forward while the other 30% is water resistance?

EDIT: Hmm that not correct.

I really don't know what I need to do. I found the power in watts, divided by the velocity in m/s and then that should be the power the ship is producing, in which 30% is lost to water resistance right?
 
Last edited:
  • #4
Delphi51 said:
Apparently 30% of the power is lost in the drive train and propeller.
Take 70% of the power and use it in the formula to find F.
Would this just mean that the force of water resistance is equal to the force of the ship?
 
  • #5
Would this just mean that the force of water resistance is equal to the force of the ship?
Yes. Motion at constant speed, so acceleration is zero and the total force on the ship is zero.
 

Related to Calculating Force on Aircraft Carrier John F. Kennedy

1. How is the force on an aircraft carrier calculated?

The force on an aircraft carrier is calculated by using Newton's Second Law of Motion, which states that force is equal to mass multiplied by acceleration (F=ma). The mass of the aircraft carrier is determined by adding up the weight of all its components, including the aircraft, crew, weapons, and fuel. The acceleration is determined by the speed and direction of the carrier's movement. Using these values, the force can be calculated.

2. What factors affect the force on an aircraft carrier?

There are several factors that can affect the force on an aircraft carrier. These include the weight and speed of the carrier, the number and weight of the aircraft on board, the direction and strength of the wind, and the friction between the carrier and the water. Other factors such as sea state and ocean currents can also have an impact on the force.

3. How does the force on an aircraft carrier impact its movement?

The force on an aircraft carrier is directly related to its acceleration. A larger force will result in a greater acceleration, which means the carrier will move faster and cover more distance in a shorter amount of time. On the other hand, a smaller force will result in a slower acceleration and a slower movement of the carrier. The force also affects the direction of the carrier's movement, as it can be used to turn the carrier in a different direction.

4. Can the force on an aircraft carrier be controlled?

Yes, the force on an aircraft carrier can be controlled to a certain extent. The carrier's engines and rudders can be used to manipulate the force and change the carrier's speed and direction. However, external factors such as wind and ocean currents can also impact the force and may limit the carrier's ability to control it completely.

5. How does the force on an aircraft carrier compare to other objects?

The force on an aircraft carrier is typically much greater than the force on most other objects. This is because of the carrier's large mass and high speed. For example, a fully loaded aircraft carrier can weigh over 100,000 tons, while a car may only weigh a few thousand pounds. Similarly, the carrier's speed can reach up to 30 knots, while a car's speed is typically around 60 miles per hour. This results in a significantly higher force on the aircraft carrier compared to a car or other smaller objects.

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