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A 2.5m long string on the same wave machine has a tension of 240N, and the wave speed is 300m/s. What is the mass of the string?

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Answer: To find the mass of the string, we can use the formula for wave speed in a string, which relates tension (T), mass per unit length (μ), and wave speed (v) as follows:

Wave speed (v) = √(T / μ)

where:

v = wave speed in m/s

T = tension in N

μ = mass per unit length in kg/m

We are given:

Wave speed (v) = 300 m/s

Tension (T) = 240 N

Now, we need to find the mass per unit length (μ) of the string. Rearrange the formula to solve for μ:

μ = T / v^2

Substitute the given values:

μ = 240 N / (300 m/s)^2

μ = 240 N / 90000 m^2/s^2

μ ≈ 0.00266667 kg/m

The mass per unit length (μ) of the string is approximately 0.00266667 kg/m.

To find the mass (m) of the entire 2.5 m long string, we can use the formula:

Mass (m) = μ * Length

m = 0.00266667 kg/m * 2.5 m

m ≈ 0.00666667 kg

The mass of the 2.5 m long string is approximately 0.00666667 kg, which is approximately 6.67 grams.

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