One end of a string of length L is tied to the celling of a lift accel...
In order to solve this problem, we need to consider the forces acting on the string.
First, let's consider the tension in the string. At the free end of the string, there is no tension as it is free to move. However, at the other end of the string (tied to the ceiling of the lift), there is a tension force acting downwards. Let's call this tension force T.
Next, let's consider the weight of the string. The weight of the string is given by the formula w = mg, where m is the linear mass density and g is the acceleration due to gravity.
Since the linear mass density of the string varies linearly from 0 to 𝜇, we can express the linear mass density as a function of the length of the string x. Let's call this function 𝜇(x).
The weight of the string at any point x can be calculated as w(x) = 𝜇(x)gx.
Now, let's consider the acceleration of the string. The entire string is accelerating upwards with an acceleration of 3g. This means that the acceleration of any point on the string is also 3g.
Using Newton's second law, we can write the equation of motion for the string as:
T - w(x) = m(x)a
where T is the tension force, w(x) is the weight of the string at point x, m(x) is the linear mass density at point x, and a is the acceleration of the string.
Substituting the values we have:
T - 𝜇(x)gx = m(x)(3g)
Since the linear mass density varies linearly from 0 to 𝜇, we can express it as 𝜇(x) = (𝜇/L)x, where L is the length of the string.
Substituting this into the equation of motion:
T - (𝜇/L)gx = m(x)(3g)
T - (𝜇/L)gx = (𝜇/L)x(3g)
T - (𝜇/L)gx = (𝜇/L)3gx
T = (𝜇/L)4gx
So, the tension in the string is given by T = (𝜇/L)4gx.
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