Kite string force, negative or positive>

In summary, the kite string exerts a 12-lb pull at a 45 degree angle with the horizontal. The horizontal and vertical components of the pull are both equal to 12√2, with the vertical component being negative due to the tension in the string pulling towards the person holding the string. However, in most cases, questions will only require you to calculate the magnitude of the force or its components, which will always be positive.
  • #1
2clients
10
0

Homework Statement



A kite string exerts a 12-lb pull (|F|) on a kite and makes a 45 degree angle with the horizontal. Find the horizontal and vertical components of F.

Homework Equations



Pythagorean

The Attempt at a Solution



12*sqrt(2) for both horizontal and negative

My question is whether to assign a positive or negative to either value? It seems that either could work with the limited assumptions in the question? Or would it be more appropriate for the y force to be negative?
 
Physics news on Phys.org
  • #2
Hi 2clients, well actually this really does depend. When you have a taught string, as we have in your question, there is a tension in the string. Now this tension can be model as acting in both direction along the string. Imagine for example you help a piece of sting in your hands and pulled both ends, there is a force stopping both hands move further apart when the string is taught, so there must be a force acting on you right had to the left, and you left hand to the right :D

So what you need to ask is in which direction do you want the tension to be acting for the purpose of you question. In the question its says it exerts a pull on the kite, so the tension will be acting down the sting towards the person holding the sting, acting away from the kite, so it will have a negative y value and and may have a negative or positive x value depending on where the person is standing relative to the kite :D

That all said, most question wouldn't ask you to work out negatives and posatives, and they will simply want to know the magnitude of a force or the magnitude of its components, which are always positive :-) hope that helped

ps sorry if you knew most of that already, obviously I don't know what you already know :D
 
  • #3


I would say that the horizontal and vertical components of the force are both positive. This is because the force is exerted in the direction of the kite's motion, which is upwards and to the right at a 45 degree angle. The negative sign in the equation may have been used to indicate that the force is acting in the opposite direction of the positive x and y axes, but it does not necessarily mean that the force itself is negative. In this case, the force is positive in both magnitude and direction.
 

Related to Kite string force, negative or positive>

1. Is kite string force negative or positive?

The force of a kite string can be both negative and positive, depending on the direction of the force. When the string is pulling the kite upwards, the force is positive. However, when the string is being pulled downwards by the weight of the kite, the force is negative.

2. How does the force of the kite string affect the flight of the kite?

The force of the kite string is essential in keeping the kite in the air. The positive force of the string pulls the kite upwards, counteracting the negative force of gravity. This tension in the string also helps the kite maintain its stability and direction in the wind.

3. Can the force of the kite string change during flight?

Yes, the force of the kite string can change during flight. As the wind speed and direction change, the force of the string may fluctuate. Additionally, the angle at which the string is held can also affect the force. For example, pulling the string at a sharper angle will increase the force, while loosening the string will decrease the force.

4. How does the length and material of the kite string affect the force?

The length and material of the kite string can affect the force in several ways. A longer string will have more surface area exposed to the wind, creating more drag and potentially increasing the force. The material of the string can also affect its strength and flexibility, which can impact the force it exerts on the kite.

5. Is there a limit to the force of the kite string?

Yes, there is a limit to the force of the kite string. The maximum force that the string can withstand without breaking is known as its tensile strength. This can vary depending on the material and thickness of the string. It is important to use a string with an appropriate tensile strength for the size and weight of the kite to avoid it breaking during flight.

Similar threads

  • Introductory Physics Homework Help
Replies
4
Views
836
  • Introductory Physics Homework Help
Replies
18
Views
993
  • Introductory Physics Homework Help
Replies
4
Views
988
  • Introductory Physics Homework Help
Replies
1
Views
3K
  • Introductory Physics Homework Help
Replies
4
Views
3K
  • Introductory Physics Homework Help
Replies
14
Views
2K
  • Introductory Physics Homework Help
Replies
31
Views
5K
  • Introductory Physics Homework Help
Replies
13
Views
4K
  • Introductory Physics Homework Help
Replies
25
Views
374
  • Introductory Physics Homework Help
Replies
1
Views
1K
Back
Top