# Finding magnitude of the tension of a cord

• schyuler2
In summary, the problem involves a 20kg block held in equilibrium by two massless cords, A and B, attached to the wall and ceiling respectively. The goal is to find the magnitudes of the tensions of the cords. Using the equations \Sigma Forces = m*a and Normal force = mg(cos \theta), we can determine that the sum of forces in the x and y directions is 0, and that the tension of cord A is equal to the weight of the block. However, the tension of cord B is still unknown. Further calculations are needed to find the magnitudes of the tensions of both cords.
schyuler2

## Homework Statement

A 20kg block is held in equilibrium by two massless cords, A, B. A is attached to the wall and B is attached to the ceiling. Find the magnitudes of the tensions of the cords.

Visual: http://i758.photobucket.com/albums/xx228/schuyler2_va/untitled.jpg?t=1260816320

## Homework Equations

$$\Sigma$$ Forces = m*a

Normal force = mg(cos $$\theta$$)

## The Attempt at a Solution

$$\Sigma$$ Forces = Tension of A + Tension of B + W + N
Tensions+Weight = ma

N = mg(cos $$theta$$)
W = 0
Tension A =?
Tension B=?

^not sure how to find the magnitudes

schyuler2 said:

## Homework Statement

A 20kg block is held in equilibrium by two massless cords, A, B. A is attached to the wall and B is attached to the ceiling. Find the magnitudes of the tensions of the cords.

Visual: http://i758.photobucket.com/albums/xx228/schuyler2_va/untitled.jpg?t=1260816320

## Homework Equations

$$\Sigma$$ Forces = m*a

Normal force = mg(cos $$\theta$$)

## The Attempt at a Solution

$$\Sigma$$ Forces = Tension of A + Tension of B + W + N
Tensions+Weight = ma

N = mg(cos $$theta$$)
W = 0
Tension A =?
Tension B=?

^not sure how to find the magnitudes
There isn't any normal force in this problem, just gravity and tension forces. Why do you say W=0 when it is given that the block has a mass of 20 kG? And since the block is in equilibrium, sum of forces is 0, because a is 0. When you sum forces, look in the x and y directions separately, or else the problem becomes vectorially overwhelming. Note that the upper cord has an x and y component of tension, while the horizontall cord has a horizontal component only.

of the tensions without knowing the angles of the cords or the distance from the wall/ceiling to the block. The equations used to solve for tension (such as \Sigma Forces = Tension + Weight) require knowledge of the angles and distances in order to accurately find the tensions. Without this information, it is not possible to accurately determine the magnitudes of the tensions. More information is needed in order to solve this problem.

## 1. How do you find the magnitude of the tension of a cord?

To find the magnitude of the tension of a cord, you will need to use the formula T = mg + ma, where T represents tension, m represents mass, g represents gravity, and a represents acceleration. This formula is also known as Newton's second law of motion.

## 2. Why is it important to find the magnitude of the tension of a cord?

It is important to find the magnitude of the tension of a cord because it helps us understand and analyze the forces acting on an object. This information is crucial in many scientific fields, such as engineering, physics, and mechanics.

## 3. What factors affect the magnitude of tension in a cord?

The magnitude of tension in a cord is affected by factors such as the weight of the object attached to the cord, the angle at which the cord is pulled, and the acceleration of the object. Other factors may include the length and elasticity of the cord, as well as external forces acting on it.

## 4. How can I measure the tension of a cord in an experiment?

To measure the tension of a cord in an experiment, you can use a device called a dynamometer or a force sensor. These tools can accurately measure the force exerted by the cord and give you the tension value in newtons (N).

## 5. Are there any safety precautions to consider when working with cords and tension?

Yes, there are some safety precautions to keep in mind when working with cords and tension. It is essential to wear protective gear, such as gloves, when handling cords to prevent injuries. Additionally, make sure to use suitable equipment and follow proper procedures to avoid overloading cords and causing them to snap or break.

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