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a particle is moving in a circle of radius R with constant speed.The time period of particle is T=1 second.In a time t=T/6,if the difference between average speed and magnitude of average velocity of particle is 2 m/sec,find the radius of circle

Respuesta :



at t=T/6, total distance covered= 2*pi*r/6  and  displacement= r

 difference of them = 2*t
so, 2*pi*r/6- r =2(1/6)=1/3

r=1/(pi-3)=7.062


Answer:

R = 7.06 m

Explanation:

As we know that time period of the particle is T = 1 s

so the angle covered by it in t = T/6 seconds is given as

[tex]\theta = \frac{2\pi}{T}t[/tex]

[tex]\theta = \frac{2\pi}{1}\times \frac{1}{6}[/tex]

[tex]\theta = \frac{\pi}{3}[/tex]

now we know that total distance moved by the particle will be

[tex]d = R\theta = R\times \frac{\pi}{3}[/tex]

now average speed is given as

[tex]v = \frac{R\times \frac{\pi}{3}}{\frac{1}{6}}[/tex]

[tex]v = 2\pi R[/tex]

now for displacement of the particle we know that

[tex]\vec d = \sqrt{R^2 + R^2 - 2(R)(R)cos\frac{\pi}{3}}[/tex]

[tex]\vec d = R[/tex]

so average velocity is given as

[tex]\vec v = \frac{R}{\frac{1}{6}} = 6R[/tex]

now we have

[tex]v - \vec v = 2\pi R - 6 R = 2 m/s[/tex]

[tex]R = \frac{2}{2\pi - 6} = 7.06 m[/tex]