A Mass Hanging From Multiple Strings

In summary, a mass of 6 kg is hanging from string 3, which is connected to string 1 and string 2. The problem asks for the tension of string 2, with available answer choices ranging from 1.2 N to 40 N. The individual forces of T1, T2, and T3 must sum to 0, with T3 being the force of gravity (58.8 N). Using this information and trigonometric equations, the tension of string 2 is calculated to be -91.44 N, which does not match any of the available answers. The method used is deemed correct, but a sign error may have caused the discrepancy. Further discussion with a teacher may be necessary.
  • #1
Null42
2
0
A mass of 6 kg is hanging from a string, named string 3. The top of this string is connected to to other strings, string one which goes straight to the left to connect with a wall, and string two which connects to the ceiling making a 40 degree angle between the ceiling and the string. The problem is asking for the tension of string 2.
The available answers are:

EDIT: Will try and provide a picture when possible.

a) 1.2 N
b) 11 N
c) 34 N
d) 3.5 N
e) 40 N


I thought I could solve the problem by considering each string a vector, representing the force of each. Since there is no movement, the sum of the Forces should equal 0.
So , T1+T2+T3=0

I figure the force of T3 to be the F_g, which should be 6 *9.8=58.8 N

Using this I then came up with the following
T1*cos(180)+T2*cos(40)+58.8*cos(270) = 0
and
T1*sin(180)+T2*sin(40)+58.8*sin(270)=0

I figured I could use the second equation most easily, since the sin(180)=0.

So, I came up with 0+(.643)T2+58.8=0
(.643)*T2=-58.8
T2=-91.44
Of course, this is nowhere close to any of the available answers, and I can't seem to wrap my head around any other way of doing it. Any help would be greatly appreciated.
 
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  • #2
Null42 said:
T1*sin(180)+T2*sin(40)+58.8*sin(270)=0

I figured I could use the second equation most easily, since the sin(180)=0.

So, I came up with 0+(.643)T2+58.8=0
(.643)*T2=-58.8
T2=-91.44
Assuming your description is accurate, the available answers are way off.

Your method is perfectly fine. You did make a sign error, but otherwise your answer is correct. (What is sin(270)?)
 
  • #3
Ahhh, yes, sorry, 58.8 * -1. Thank you for that. I guess I'll just have to discuss it with the teacher. Thanks!
 

What is a mass hanging from multiple strings?

A mass hanging from multiple strings refers to a physical setup where a single object, typically a weight or mass, is suspended from multiple strings or threads attached to a fixed point. This setup is often used in physics experiments to study the effects of gravity, tension, and other forces on the mass.

Why is a mass hanging from multiple strings used in experiments?

The setup of a mass hanging from multiple strings allows for the manipulation and control of various forces acting on the mass. This allows scientists to observe and measure the effects of these forces on the mass, providing valuable insights into the laws of physics.

What factors affect the motion of a mass hanging from multiple strings?

The motion of a mass hanging from multiple strings is affected by several factors, including the length and tension of the strings, the mass of the object, and the gravitational force acting on the object. Other factors such as air resistance and friction may also play a role in the motion of the mass.

How is the motion of a mass hanging from multiple strings calculated?

The motion of a mass hanging from multiple strings can be calculated using principles of mechanics, such as Newton's laws of motion and the equations of motion. Factors such as the mass, forces acting on the object, and the length and tension of the strings are taken into account to determine the acceleration, velocity, and position of the mass over time.

What are some real-world applications of a mass hanging from multiple strings?

A mass hanging from multiple strings is used in various real-world applications, such as weighing scales, pendulum clocks, and suspension bridges. In physics and engineering, this setup is also used to study and analyze the behavior of structures and materials under different forces and conditions.

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