a. The expression for the tension in the string is T = mg
b. The expression for the tension in the chain is T = 2mg
To solve the problem, we need to know what tension is.
<h3>What is tension?</h3>
This is the opposing force in a stretched material.
<h3>a. Tension in the string</h3>
The expression for the tension in the string is T = mg
Since the string supports the weight of the object, the tension in the string equals the weight of the particle.
Let
- T = tension in sring and
- W = weight of particle = mg where
- m = mass of particle and
- g = acceleration due to gravity
So, T = W
T = mg
So, the expression for the tension in the string is T = mg
<h3>b. Tension in chain</h3>
The expression for the tension in the chain is T = 2mg
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Since the chain supports both strings, the tension in the chain equals the tension in both strings.
Let
- T' = tension in chain and
- T = tension in each string
So, T' = T + T
T' = 2T
T' = 2W
T' = 2mg
So, the expression for the tension in the chain is T = 2mg
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Learn more about tension here:
brainly.com/question/24994188
which is further simplified to 
which is 20.