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One end of a string is fixed. An object attached to the other end moves on a horizontal plane with uniform circular motion of radius R and frequency f. The tension in the string is Fs . If both the radius and frequency are doubled, the tension is what

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Answer:

If both the radius and frequency are doubled, then the tension is increased 8 times.

Explanation:

The radial acceleration ([tex]a_{r}[/tex]), measured in meters per square second, experimented by the moving end of the string is determined by the following kinematic formula:

[tex]a_{r} = 4\pi^{2}\cdot f^{2}\cdot R[/tex] (1)

Where:

[tex]f[/tex] - Frequency, measured in hertz.

[tex]R[/tex] - Radius of rotation, measured in meters.

From Second Newton's Law, the centripetal acceleration is due to the existence of tension ([tex]T[/tex]), measured in newtons, through the string, then we derive the following model:

[tex]\Sigma F = T = m\cdot a_{r}[/tex] (2)

Where [tex]m[/tex] is the mass of the object, measured in kilograms.

By applying (1) in (2), we have the following formula:

[tex]T = 4\pi^{2}\cdot m\cdot f^{2}\cdot R[/tex] (3)

From where we conclude that tension is directly proportional to the radius and the square of frequency. Then, if radius and frequency are doubled, then the ratio between tensions is:

[tex]\frac{T_{2}}{T_{1}} = \left(\frac{f_{2}}{f_{1}} \right)^{2}\cdot \left(\frac{R_{2}}{R_{1}} \right)[/tex] (4)

[tex]\frac{T_{2}}{T_{1}} = 4\cdot 2[/tex]

[tex]\frac{T_{2}}{T_{1}} = 8[/tex]

If both the radius and frequency are doubled, then the tension is increased 8 times.

If both the radius and frequency are doubled, then the tension will be increased 8 times.

 

From kinematic formula:

[tex]\bold {a_r = 4\pi r^2 \times f^2 \times R^2}[/tex] .............................. (1)

Where:  

f - Frequency,    

R - Radius of rotation,  

From Second Newton's Law,

[tex]\bold {\sum F = T = m\times a_r }[/tex] ......................... (2)

Where

m is the mass of the object,

From equation 1 and 2,

[tex]\bold {T = m\times 4\pi r^2 \times f^2 \times R^2}\\[/tex] .................... (3)

From equation, tension is directly proportional to the radius and the square of frequency.

Then, if radius and frequency are doubled, then the ratio between tensions is:

[tex]\bold {\dfrac {T_2}{T_1} = (\dfrac {F_2}{F_1})^2 \times \dfrac {R_2}{R_1} = 4 \times 2 = 8 }[/tex]  

   

Therefore, If both the radius and frequency are doubled, then the tension will be increased 8 times.

To know more about frequency,

https://brainly.com/question/24864018

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